CYP3A4 Inhibitor Research Articles

Population Pharmacokinetics and Exposure-Response Analyses from Phase I-III Studies Support Copanlisib Dose Selection in Relapsed Indolent Non-Hodgkin Lymphoma

Introduction: Copanlisib is a novel PI3K inhibitor that is approved for single-agent treatment of relapsed follicular lymphoma in patients (pts) who have received ≥2 systemic therapies. In the pivotal Phase III CHRONOS-3 study, pts with relapsed iNHL were randomized to copanlisib at the approved maximum tolerated dosing regimen of 60 mg administered on days 1, 8, and 15 of a 28-day cycle in combination with standard rituximab (C+R) or placebo plus rituximab (P+R) and demonstrated superior progression-free survival (PFS) of C+R vs P+R (hazard ratio [HR]: 0.52; Matasar et al. Lancet Oncol 2021). In an updated 1-year follow-up analysis, the benefit of C+R was confirmed in the overall relapsed iNHL population (Zinzani et al. EHA 2022). No dedicated dose-finding studies have been undertaken to investigate copanlisib dose selection when used in combination with rituximab; however, initial safety assessments demonstrated acceptable tolerability. We investigated popPK and ER relationships for copanlisib efficacy and safety from a pooled analysis, with particular focus on the 1-year follow-up of CHRONOS-3 to confirm copanlisib dose selection. Methods: A copanlisib comprehensive popPK model was developed from 712 pts across 9 copanlisib clinical Phase I-III studies. Demographic, laboratory, and co-medication covariates were investigated for their influence on copanlisib between-patient PK variability. Individual static and time-varying exposure estimates for pts enrolled in CHRONOS-3 were derived to investigate relationships to efficacy (PFS) and key treatment-emergent safety events using Cox proportional hazards (CPH) and multivariate logistic regression analyses after accounting for predefined potentially prognostic demographic, laboratory, and/or disease-related baseline covariates. Results: Copanlisib PK was best described by a 3-compartment PK model with first-order elimination following intravenous infusion. Copanlisib PK was dose proportional and time independent, with no accumulation with the approved dosing regimen. Statistically selected covariates influencing copanlisib PK included rifampin (strong CYP3A inducer) and itraconazole (strong CYP3A inhibitor) co-administration and mild or worse hepatic impairment, confirming the results of dedicated clinical pharmacology studies. Additional covariates influencing copanlisib PK included female sex, residence in Japan, and a CHRONOS-3 study effect, with the majority of covariates or subpopulations defined by sex, age, body weight, renal function, and geographic region showing exposure variations not exceeding traditional bioequivalence ranges (80-125%). In CHRONOS-3, CPH analyses demonstrated a statistically significant, positive ER relationship for PFS for all 3 time-varying copanlisib exposure estimates (average concentration [Cavg] over 2 weeks [Cavg2wk]: p=0.002; 4 weeks [Cavg4wk]: p=0.004; and 8 weeks [Cavg8wk]: p=0.002), along with a near-significant relationship for area under the curve from 0 to 168 hours (AUC(0-168)nd) [p=0.023] (Figure 1). Therefore, greater copanlisib exposure was associated with prolonged PFS, while lower copanlisib doses may result in reduced efficacy in relapsed iNHL. CPH and/or logistic regression analyses demonstrated no significant ER relationship for investigated safety events (serious adverse events [AEs], grade ≥3 treatment-emergent AEs, hyperglycemia, hypertension, diarrhea, nausea, fatigue, lung infections, and neutropenia of any grade). Thus, lower starting doses of copanlisib are not anticipated to improve safety and tolerability. ER analyses support the overall positive benefit/risk assessment of copanlisib reported from the clinical efficacy and results of CHRONOS-3 in iNHL. Conclusion: PopPK and ER analyses substantiate administration of a dosing regimen of copanlisib 60 mg on days 1, 8, and 15 of a 28-day cycle in the relapsed iNHL population. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Phase II Trial of Venetoclax (Ven) in Combination with Azacitidine (AZA) As Maintenance Therapy for High-Risk Acute Leukemia Following Allogeneic Stem Cell Transplantation (SCT)

Introduction: Allogeneic SCT remains the only potentially curative therapy for acute leukemia patients but with inferior outcomes for high-risk patients. Prior data on maintenance therapies, including AZA, have yielded conflicting results on its efficacy to improve outcomes. Considering the clinical efficacy of VEN in acute myeloid and lymphoid leukemia (AML/ALL) with its known tolerability when used with AZA, we thought VEN and AZA might be an attractive maintenance strategy to improve outcomes after SCT. Methods: This is a single center, open label, Phase II clinical trial to assess the safety and efficacy of VEN with AZA as maintenance therapy after SCT. Inclusion criteria was 1) high risk AML or B cell and T cell ALL or mixed phenotype leukemia, 2) absolute neutrophil count >/= 1.0 x 109/L and platelet >/= 30 x 109/L without any support, 3) absence of active graft versus host disease (GvHD) and infection, 4) absence of minimal residual disease at enrollment. Treatment consisted of up to 12 cycles of VEN 100 mg on Days 1-7 with AZA 32 mg/m 2/day IV/SC on Days 1-5 every 28 days. VEN dosing was adjusted for patients on concomitant CYP3A inhibitors or those with severe cytopenias. After the first 11 patients enrolled, due to myelosuppression observed, VEN dose was changed to 50 mg on days 1-7 if patients were on posaconazole. Treatment delays, up to 70 days, were allowed by toxicity. The primary objectives are relapse-free survival (RFS) after initiation of VEN and AZA and the safety and tolerability of the combination. The study has been ongoing. Results: The study enrolled a total of 30 patients (27 AML, 3 ALL). Demographics across all AML patients included mean age 52 years (range: 40-74), 67% males, 15% second SCT, 48% in first complete remission (CR1) at SCT, 41% adverse risk by European Leukemia Net classification. The majority (63%) received a myeloablative intensity conditioning regimen using intravenous busulfan. The three ALL patients were younger with mean age of 35 and all were in CR1 at SCT. The median time to start the maintenance treatment was 70.5 days (range, 42-103). As of the data cutoff date of 13 July 2022, patients completed a median of 4 cycles (range, 1-12) of study treatment with 9 patients (30%) remaining on study treatment. The primary reasons for study treatment discontinuation among 21 patients were complications like myelosuppresssion, infections and GvHD in 11, relapse in 6 and completion of 12 cycles of treatment in 4. The median follow-up time was 8.67 months (95% CI, 7.23 to 13.6).The median RFS and OS were not reached. The estimates of RFS and OS at 1-year were 69.2% (95% CI, 52.1% to 91.8%) and 90.2% (95%CI, 78% to 100%), respectively, after the initiation of VEN and AZA maintenance (Figure 1&2). Assuming a Bayesian Poisson-Gamma Model with a Gamma (1,1) prior; the mean number of grade≥3 treatment related adverse events (AEs) per patient was estimated. The mean number of AEs were 1.87 (range, 0-8) for decreased white blood cell count; 1.68 (range, 0-7) for decreased absolute neutrophil count; 1.06 (range, 0-6) for decreased platelet count; 0.55 (range, 0-6) for anemia; 0.13 (range, 0-1) for pneumonia and 0.06 (range 0-1) for each event of febrile neutropenia, maculopapular rash, respiratory failure and secondary graft failure (GF). The secondary GF was observed in one patient after the 4th cycle of treatment leading to discontinuation of study treatment. No patient died to due to treatment related AEs. Due to frequent and prolonged myelosuppression observed, 9 patients (30%) required dose reduction of VEN; mostly right after the first cycle of treatment (6 of 9 patients). After the protocol amendment for VEN to be given as 50 mg on days 1-7 on posaconazole, the requirement for dose changes decreased though still some patients required lower doses of VEN (as 30 mg on days 1-5) on subsequent cycles. Conclusion: Post-SCT maintenance therapy with VEN/AZA was safe and tolerable with favorable results in patients with high-risk AML and ALL. The majority of reported AEs was related to myelosuppression which is a known complication of VEN. Many patients required dose modification of VEN and treatment delays between cycles, highlighting the importance of monitoring these patients very closely. On the other hand, the observed RFS and OS data were highly encouraging compared to the historical outcomes for this high-risk group of patients although longer follow-up is needed. The study has been ongoing. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Venetoclax Added to Cladribine (CLAD) + Low Dose AraC (LDAC) Alternating with Azacitidine (AZA) Is Highly Active As Frontline Therapy in Older Patients with Newly Diagnosed Acute Myeloid Leukemia in a Phase 2 Study

Background The combination of venetoclax with AZA for patients with newly diagnosed AML who are older or unfit for intensive chemotherapy significantly improves remission rates and survival compared to AZA alone. A low-intensity backbone combining venetoclax with cladribine (CLAD) plus low-dose araC (LDAC) alternating with HMA has demonstrated encouraging results in older patients with newly diagnosed AML (Kadia TM, et al. J Clin Oncol. 2022). Here we report an updated cohort of patients with longer-term follow up treated on the phase 2 clinical trial of venetoclax added to CLAD/LDAC alternating with AZA. Methods This is a phase 2 study (NCT03586609) investigating the combination of venetoclax with CLAD/LDAC alternating with AZA in older (age ≥ 60 years) or patients <60 years that are unfit for intensive chemotherapy with newly diagnosed AML (excluding APL, CBF). The primary objective was composite complete response rate (CRc; CR+CRi); secondary endpoints were overall survival (OS), disease-free survival (DFS), overall response rate (ORR), and toxicity. Induction was with cladribine 5 mg/m2 IV on D1-5 and araC 20mg SQ BID on D1-10. Consolidation/maintenance consisted of 2 courses of cladribine 5 mg/m2 IV on D1-3 and araC 20 mg SQ BID on D1-10 alternating with 2 cycles of AZA 75 mg/m2 on D1-7, for up to 18 courses. Venetoclax 400 mg was added for each course with dose adjustments for concomitant CYP3A inhibitors. Venetoclax was given for 21 days during induction and for 7-14 days for consolidation depending on measurable residual disease (MRD) and tolerability. One cycle was 4 weeks and up to 2 cycles of induction were allowed. Results A total of 93 patients were treated on study with a median age was 68 years (range: 57 - 84); 28 (30%) patients were ≥ 70 yrs and 1 patient <60, unfit for intensive chemotherapy was enrolled. 29 (31%) patients had secondary or therapy related AML. 52 (56%) had diploid cytogenetics with 11 (12%) having adverse cytogenetics at enrollment. By European Leukemia Network (ELN) risk, 24%, 24%, and 53% were favorable, intermediate, and adverse risk, respectively. The most commonly mutated genes were DNMT3A in 28 (30%), NPM1 in 26 (28%), RAS in 23 (25%), TET2 in 22 (24%), and IDH2 in 20 (22%). TP53 was mutated in 8 (9%) patients. Among 93 evaluable patients the CRc rate was 92%. Best response was CR in 72 (78%), CRi in 13 (14%), no response in 5 (5%), and death in 2 (2%) patients. In responding patients with a bone marrow sample evaluable for assessment of MRD by flow cytometry, 71/85 (84%) achieved MRD negativity while on study. Responses were preserved across ELN risk groups with the CRc (CR/CRi) rate of 95% (86%/9%), 95% (82%/14%), and 90% (73%/17%) for patients with ELN favorable, intermediate, and adverse risk, respectively. CRc rate for TP53 mutated disease was 88% (7/8, 86% MRD negative) and for NPM1 mutated disease was 96% (25/26, 100% MRD negative). 35 (41%) responders received a subsequent allogeneic stem cell transplantation (alloSCT). Early mortality was low with two patients (2%) dying within 4 weeks and five patients (5%) dying with in 8 weeks. The most frequent grade 3/4 non-heme adverse events were febrile neutropenia (n=12), infection (n=7), atrial fibrillation (n=2), and allergic reaction (n=2). One patient developed grade 4 tumor lysis syndrome. With a median follow up of 22.8 months, the median duration of response (DOR) is not reached (95% CI: NE - NE months). Estimated 12- and 24-month DOR are 88.4% (95% CI: 81.0 - 96.4%) and 81.0% (95% CI: 71.0 - 92.4%), respectively. Median disease-free survival (DFS) is not yet reached (95% CI: 24.5 - NE months). Estimated 12- and 24-month DFS are 76.0% (95% CI: 66.8 - 86.4%) and 63.4% (95% CI: 52.1 - 77.1%), respectively. Median overall survival (OS) is not yet reached (95% CI: 25.4 - NE months). Estimated 12- and 24-month OS are 75.7% (95% CI: 66.9 - 85.7%) and 68.3% (95% CI: 58.1 - 80.1%), respectively (Figure). Conclusion Venetoclax added to CLAD/LDAC alternating with AZA is a highly effective, lower-intensity regimen which is well tolerated among older patients with newly diagnosed AML, producing high CRc and MRD negative remission rates and is effective in transitioning older adults to alloSCT. The rates of DFS and OS are encouraging. Further study of this non-anthracycline containing regimen is warranted in older patients both fit and unfit for intensive chemotherapy as a safe and effective induction treatment strategy. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

A Chemo-Free Bridge-to-Transplant Strategy with Venetoclax and Azacitidine for NPM1-Mutated Acute Myeloid Leukemia in Molecular Failure

Background: In patients (pts) with NPM1-mutated acute myeloid leukemia (AML) fit for intensive chemotherapy, the persistence, reoccurrence, or progression of NPM1mut transcript identifies poor chemotherapy responders that require allocation to allogeneic stem cell transplantation (alloSCT). Currently, there is no standard of care for pts in molecular failure and the proper bridging strategy to alloSCT still needs to be defined. The combination of Venetoclax (VEN) and Azacitidine (AZA) offers an alternative chemo-free strategy with favorable toxicity profile in NPM1mut AML, a molecular subset exquisitely sensitive to VEN. Aims: To characterize a series of NPM1mut AML pts in molecular failure who received VEN-AZA as bridge-to-transplant treatment strategy. Methods: We explored the off-label combination of Venetoclax (VEN) and Azacitidine (AZA) in 9 NPM1mut fit AML pts in molecular failure after intensive chemotherapy eligible for alloSCT, treated at 4 Italian Hematology Institutions. Disease was monitored on bone marrow (BM) with NPM1mut-specific qRT-PCR assay. The quantitative detection limit of the assays was 0.01%. Complete response with minimal residual disease negativity (CR-MRDneg) was defined as ratio NPM1mut/ABL x 100 transcript < 0.01 copies Results: Of the 9 pts analyzed 4 (44%) were female, median age at diagnosis was 56 years (range 41-66) and 58 years (range 43-68) at VEN-AZA therapy. Eight of the 9 pts had ELN2017 favorable-risk AML (2 pts with concomitant FLT3-ITDlow and 1 FLT3-TKD) and 1 pt had intermediate-risk AML (FLT3-ITDhigh). Pts received in median 4 (range 2-5) cycles of front line chemotherapy. Seven pts were treated for molecular relapse and 2 for molecular persistence/progression. All pts received full VEN dosage (400 mg/die or 100 mg/die if concomitant strong CYP3A4 inhibitor) and AZA 75 mg/m2/die s.c. in 5- or 7-day schedule. All pts but 1 performed VEN ramp-up. Pts received a median of 3 cycles (range 1-4). No AZA dose reduction occurred. Median VEN duration during cycle (C)1 was 25 days (range 14-28), 21 days (range 7-28) in C2, 24.5 days (range 7-28) in C3 and 25.5 days (range 19-28) in C4. VEN dosage reductions were due to hematological toxicity ≥ G3 in 60% of cases and in 40% for logistic reasons. The observed ≥ G3 toxicities were neutropenia in 4/9 (44%) pts, 1 thrombocytopenia and 1 febrile neutropenia, managed out-patient. No tumor lysis syndrome was observed. Best response to VEN-AZA was CR MRDneg (NPM1mut undetectable) in 7/9 (78%) pts, reached after a median of 2 cycles (range 1-4). Importantly, no pts relapsed ongoing therapy; 1 pt, notably the FLT3-ITDhigh pt, in CR MRDpos presented molecular progression after C3. Median time from VEN-AZA start to alloSCT was 4.3 months (range 1.7-8.1). At pre-transplant evaluation 6/9 (67%) pts were in CR MRDneg. Eight of 9 pts received myeloablative conditioning and 1 pt received reduced-intensity conditioning. With a median follow-up from alloSCT of 9.3 months (range 2.4-24.0) all patients are alive and 8/9 (89%) in CR MRDneg. Four pts presented NPM1mut reoccurrence after alloSCT: in 2 pts CsA tapering achieved molecular negativity, 1 pt underwent prophylactic therapy with sorafenib and 1pt is currently in CR MRDpos. In no pts FLT3 mutations were detected and, most importantly, no patients experienced morphological relapse. Conclusions: VEN-AZA demonstrated to be a safe and effective bridging regimen for NPM1mut AML pts in molecular failure, allowing to achieve deep responses in the majority of pts at the expense of low toxicity. These preliminary encouraging results will be explored in the GIMEMA AML2521 trial in the same patient subset (clinicaltrials.gov NCT04867928).

Itacitinib and Corticosteroids As Initial Treatment for Chronic Graft-Versus-Host Disease: Phase 1/2 Results from Gravitas-309

Background: Itacitinib is a potent, selective oral Janus kinase (JAK) 1 inhibitor with broad anti-inflammatory activity. GRAVITAS-309 was designed as a 2-part, multicenter, randomized trial to assess the efficacy and safety of itacitinib in combination with corticosteroids (CS) as first-line treatment for moderate or severe chronic graft-versus-host disease (GVHD). We describe preliminary results from the open-label, dose-finding portion of the study. Methods: The study initially investigated itacitinib at doses of 200 mg once daily (qd; n=11) and 300 mg qd (n=10) in combination with CS. Both doses were well tolerated. The trial was then expanded to test itacitinib 400 mg qd and 300 mg twice daily (bid); the initial 300-mg qd cohort was expanded, and a CS monotherapy cohort was added (Figure 1). The expected CS starting dose was 0.5-1 mg/kg per day prednisone (or methylprednisolone equivalent) with a dose taper initiated on Day 14 or earlier during the second week of treatment and following published recommendations (Flowers and Martin. Blood. 2015;125[4]:606-15). Itacitinib dosage was initially reduced by 100 mg when given concomitantly with a strong CYP3A4 inhibitor (sCYP3A4i; eg, azole antifungals). A total of 140 patients (pts) (35/treatment group) with moderate or severe chronic GVHD were to be randomized 1:1 using chronic GVHD risk status (moderate vs severe) as a stratification factor. The primary objective was to identify the appropriate dose and schedule of itacitinib for further development. The data cutoff was January 31, 2022. Results: 103 pts were enrolled and received at least one dose of itacitinib. The cohorts were well balanced for pt and disease characteristics. Median age was 57 years (range, 23-76) for the itacitinib cohorts and 59 years (range, 28-75) for the CS cohort. Approximately two-thirds of pts had moderate chronic GVHD. At the time of data cut, 39 (38%) pts in the itacitinib cohorts and 10 (28%) pts in the CS cohort continued study treatment. Median duration of study treatment was 27-28 weeks for the itacitinib cohorts (including 13-16 weeks of concomitant CS) and 17 weeks for the CS cohort. The itacitinib 300-mg bid dose cohort was discontinued early due to malignancy relapse occurring in 4/29 (14%) pts and more pts requiring dose reductions compared with the 400-mg qd and 300-mg qd cohorts (28% vs 17% and 8%, respectively), mostly due to cytopenias. Incidence of grade ≥3 treatment-emergent adverse events (AEs) was higher in the itacitinib cohorts than with CS (65% vs 31%) and were reported most commonly in the system organ classes of infections (44% vs 6%) and blood and lymphatic system disorders (23%-34% vs 6%). Cytomegalovirus (CMV) infections occurred in 10%-15% of pts in itacitinib cohorts (including CMV pneumonia [n=3], esophagitis [n=1], enteritis [n=1]) vs 3% with CS. The all-cause mortality rate was 14%-18% in itacitinib cohorts vs 11% with CS, with infections the leading cause. The overall response rate (ORR) at 6 months was 46% (complete response [CR], 14%) with 300-mg qd and 53% (CR, 32%) with 400-mg qd, vs 36% (CR, 18%) with CS. A preliminary exposure-response analysis showed a bell-shaped curve with maximum efficacy decreasing at higher exposures, consistent with increasing incidence of AEs. 60%-70% of patients received coadministration with a sCYP3A4i at any time point during study treatment, which increased itacitinib exposure across all doses, requiring dose reduction by 200 mg qd. Conclusion: Preliminary results for first-line treatment of moderate or severe chronic GVHD showed an increase in ORR and CR rate with itacitinib + CS vs CS alone in both the 300-mg qd and 400-mg qd cohorts, at the expense of increased rates of cytopenias, infections, and mortality. This benefit:risk ratio does not support moving the combination of itacitinib + CS to a later phase of development in first-line therapy of chronic GVHD. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

High Response and Prolonged Treatment-Free Remission after a Short-Course of Modified Intensive Chemotherapy and Venetoclax in Elderly AML: An Updated Analysis of the Caveat Trial

Background Venetoclax (VEN) plus azacitidine has an established role in the management of older patients (pts) with AML (DiNardo, NEJM 2020). To explore the feasibility of intensive chemotherapy combined with VEN in older pts with newly diagnosed AML, we conducted the CAVEAT trial (Chua et al, JCO 2020). We now present an updated analysis of this trial (with >3 years median follow-up), reporting on the optimal dose of VEN with chemotherapy, with and without posaconazole (POSA), the deliverability of consolidation therapy, characteristics of treatment failure and observation of substantial treatment-free remission in subsets of pts using this time-limited, short-course regimen. Methods The CAVEAT study enrolled pts aged ≥65 years with de novo or secondary/therapy-related AML (sAML) considered suitable for intensive chemotherapy. Five VEN dose escalation cohorts (50-100-200-400-600 mg) were explored initially. Two additional cohorts examined the safety of adjusted dosing of VEN (50 or 100 mg) during anti-fungal prophylaxis with the strong CYP3A4 inhibitor POSA. For induction, VEN was administered over 14 days, commencing with a 7-day pre-chemo dose ramp-up, followed by a 7-day overlap with 5+2 chemotherapy (cytarabine 100mg/m2/d IVI d1-5 and idarubicin 12mg/m2 IV d2-3). Consolidation (CONS) with 2+1 chemotherapy (below), followed by up to 7 cycles of VEN monotherapy maintenance was planned. Results Data cut-off: 31MAR2022. A total of 69 pts are included in this analysis (first pt 17JUL2016, last pt 15MAY2020). Median age was 71 years (range 63-80). Poor risk features included sAML (42%), adverse karyotype (28%) and prior HMA (23%). From the dose escalation phase, the VEN 600 mg cohort was well tolerated (30-day mortality 6%). Induction with VEN-POSA (n=18) was also well tolerated (30-day mortality 0%) with 3 DLTs observed: 2 hematologic (1 in each cohort) and 1 due to pulmonary infiltrates occurring on d2 induction (suspected to be allopurinol hypersensitivity). No clinical TLS was observed. Although hematologic recovery was satisfactory after VEN-POSA induction, recovery was considerably longer in the VEN (100mg)-POSA cohort after CONS1 compared to VEN (50mg)-POSA for both neutrophils (median 64 vs 44d to 0.5 x109/L) and platelets (median not reached vs 26d to 50 x109/L). Therefore, if POSA is used concurrently, VEN 50 mg is recommended. Alternatively, if VEN 600 mg is used, POSA should commence only after completion of VEN. In the VEN 600 mg cohort, significant delays in hematological recovery were also observed after multiple rounds of attenuated CONS (VEN d1-14, bolus doses of cytarabine 100 mg/m2 d1-2, idarubicin 12 mg/m2 on d1), limiting deliverability (median CONS cycles 1; range 1-3). By intention-to-treat, the overall response (CR/CRi) rate was 73%. CR/CRi was 90% in de novo AML (vs 51% in sAML), 84% in intermediate karyotype (vs 69% in adverse), 76% and 83% in NPM1 and IDH2 mutant AML, respectively. With a median follow-up of 37 months (m), the median overall survival (OS) was 15.4m. Median OS was 31.3m in de novo AML (40% alive at 36m) and 30.3m in intermediate karyotype AML (38% alive at 36m). In the VEN 600 mg cohort, median OS was 24.1m (36% alive at 36m). As CAVEAT delivered just one intensive cycle of therapy, followed by limited post remission therapy (median time on therapy 7.7m), we next assessed the duration of treatment-free remission (TFR) among responders. Among pts achieving CR/CRi, 20/51 (39%) experienced TFR (Fig 1). The median TFR was 22.1m (range 4.6-48.3m). At data cut-off, 12 (24%) have ongoing TFR. Notably, 15/20 (75%) with TFR had an NPM1 or IDH2 mutation at diagnosis. 11 out of 14 evaluable pts with NPM1 mutation had mutation clearance by RT-qPCR, including 3 with NPM1 negative disease at time of failure (1 refractory, 2 relapse). Two pts with persistently mutated NPM1 at relapse had a concomitant FLT3-ITD or KIT mutation. The mutation landscape at relapse is shown (Fig 1) Conclusion VEN combined with modified intensive chemotherapy achieved high response rates in older pts with newly diagnosed AML. With long-term follow-up, the time-limited CAVEAT schedule enabled pts, especially with mutated NPM1 or IDH2, to experience a durable treatment-free remission. Cumulative hematological toxicity is limiting, prompting us to now explore non-anthracycline CONS (low dose cytarabine 20mg/m2 SC d1-10 + VEN 400mg d1-7, for up to 4 cycles), followed by VEN monotherapy (400mg D1-14 q28d cycle x7). Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Q-TWiST in Venetoclax-Based Regimens in Elderly Patients with AML: A Quality-Adjusted Analysis

Introduction: Non-intensive venetoclax-based regimens are the current standard of treatment for acute myeloid leukemia (AML) in the elderly. Phase 3 VIALE-C (LDAC vs. LDAC+Ven) and VIALE-A (Aza vs. Aza+Ven) trials showed improved median overall survival (OS) from 4.1 to 7.2 months (VIALE-C) and from 9.6 to 14.7 months (VIALE-A), with serious adverse events (SAEs) in 73% low-dose AraC (LDAC), 83% (Aza + Ven), 66% (LDAC + Ven). Quality of the time gained with these regimens is particularly important in this population. Q-TWiST is a useful tool to adjust the OS to quality time without symptoms or toxicity. This kind of analysis has been previously published in newly diagnosed AML in glasdegib + LDAC vs LDAC trials (Solem CT, 2020), and in the CPX-352 vs 7+3 (Cortes JE, 2021) trial. However, venetoclax-based non-intensive regimens have not been analyzed with this method. Methods: We performed a retrospective, longitudinal analysis of data gathered from a single-center cohort. All newly diagnosed, >60 years old patients with upfront management with venetoclax-based non-intensive chemotherapy combined with LDAC or hypomethylating agents (HMA) at our institution were included. TOX time was defined as the period of time before remission and/or time with serious adverse events (SAE) as defined by Office for Human Research Protections (OHRP) guidance (2007). REL time was defined as time from relapse until death, last follow-up or the start of a second line treatment, TWiST was defined as the time in remission and without SAEs. Q-TWiST analysis was performed as previously described (Solem CT, 2020). Results: We included 17 patients, 58.8% were male, mean age was 74 (70-78) years. The diagnosis was de novo AML in 52.9%, and secondary AML in 46.9%. European LeukemiaNet (ELN) risk was favorable in 5.8%, intermediate in 11.7% and adverse in 41.1%, 35.2% was unknown, FLT3-ITD mutations were present in 23.5%. 25% of the population had basal ECOG performance status ≥3, HCT-CI score was ≥3 in 47%. Considering the patients with baseline geriatric assessment: 14.2% were frail, 42.8% pre-frail and 42.8% robust. Venetoclax was combined with azacitidine in 35.2% and LDAC in 64.7%, 11.7% received additional midostaurin. Venetoclax dose was 100 mg/day in combination with strong CYP3A4 inhibitors (mainly itraconazole) in all patients. By last cycle, venetoclax was adjusted to <28 days in 76.6% of patients. Azacitidine dose was adjusted in 60% of patients, and LDAC in 9%. 76% of patients achieved complete remission (CR) or complete remission with incomplete hematological recovery (CRi) with the treatment, 23.5% had no response and 28% relapsed. With a mean follow up of 42.4 (25.7-59.1), mean OS was 43.1 (95% IC 26.6-59.6), progression free survival (PFS) 37 (95% IC 19.1-54.8), Q-TWiST 36.3 (95% IC 19.7-53), and TWiST 30.3 (95% IC 13.5-47.1) weeks. Other variables related to toxicity are shown in table 1. Comparison with previously reported Q-TWiST with LDAC and 7+3 as frontline therapy in the elderly is described in Figure 1. Conclusions: the Q-TWiST in our unselected population was better than the Q-TWiST described for LDAC arm in the glasdegib trial, this is striking considering the comparison between real world data in a low-income setting with clinical trial population. This suggests that venetoclax-based non intensive chemotherapy not only offers longer OS but also longer quality-adjusted time compared to previous standard to this vulnerable population. When compared to 7+3 regimens the Q-TWiST was slightly shorter in our cohort,probably associated with the inclusion criteria of the trial, including ability to tolerate 7+3 regimen and an age limit of 75 years, which different from our population. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Phase 2 Study of ASTX727 (cedazuridine/decitabine) Plus Venetoclax in Patients with Relapsed/Refractory Acute Myeloid Leukemia (AML) or Previously Untreated, Elderly Patients with AML Unfit for Chemotherapy

Background: ASTX727, an oral formulation of the fixed dose combination of decitabine and cytidine deaminase inhibitor cedazuridine (35 mg/100 mg), has been recently approved for the treatment of patients (pts) with myelodysplastic syndrome. Combination of the hypomethylating agents (decitabine or azacytidine) with venetoclax (Ven), an orally bioavailable BCL-2 inhibitor, is the standard of care for treating pts with AML unfit for intensive induction chemotherapy based on age and/or comorbidity. We are investigating whether a total oral therapy regimen of ASTX727+ven is feasible and safe. Methods: Pts aged ≥18 years with relapsed/refractory AML (R/R) or pts with AML (excluding acute promyelocytic leukemia) aged ≥ 75 or 18 -74 with comorbid conditions prohibiting intensive chemotherapy (frontline, FL) are eligible to participate. Other eligibility criteria included adequate renal and hepatic function and absence of uncontrolled infections or other uncontrolled comorbidities and an ECOG performance status (PS) of ≤2. ASTX727 is administered orally daily on days 1-5 of each treatment cycle and Ven on days 1-28 of the first cycle after a dose ramp up of 100-200-400 mg over 3 days (with tumor lysis prophylaxis precautions and with ven dose adjustments as needed based on concurrent CYP3A4 inhibitor therapy such as azole antifungals). A bone marrow exam is performed on day 21±3 days of first cycle and ven is held if blasts cleared to <5% to allow count recovery. Bone marrow exam is repeated on day 28±7 days to document response. Cycles are repeated every 4-8 weeks depending on count recovery and venetoclax is administered for 21 days in subsequent cycles. Dose adjustments of both ASTX727 and ven are permitted depending on tolerance. Results: As of July 11th, 2022, a total of 37 pts (21 FL, 16 R/R) have been enrolled on the study. The median age is 75 years (range, 46-92); 73 in the FL cohort and 75.5 in the R/R cohort. Nine (43%) frontline pts were older than 75 years including 8 pts (38%) ≥80 years. In the R/R cohort, 11 pts (69%) were 70-80 years. The median PS was 1 (range 0-3). The R/R cohort had a median 2 of prior treatments (range, 1-4). In the frontline cohort, 4 pts (19%) had normal cytogenetics, 9 (43%) a complex karyotype; and 7 (33%) other abnormalities including trisomy 8 and miscellaneous. In the R/R cohort, 44% had normal karyotype, 38% complex karyotype and 13% other. Mutations of note in the frontline cohort were TET2 (35%), ASXL1 (30%), RUNX1 (24%), TP53 (16%), and DNMT3A (11%). The overall response including complete response (CR), CR with incomplete count recovery (CRi) and morphological leukemia free state (MLFS) in the frontline cohort is 65% (4 CR, 6 CRi, 1 MLFS and 4 non-responders and 2 not evaluable). 2 pts received only one day of therapy for severe adverse events unrelated to therapy (1 due to ischemic stroke, 1 due to septic shock) and were not evaluable for response. In the R/R cohort, the overall response rate is 53% (6 CR, 1 CRi, 1 MLFS with 7 non-responders). Both cohorts received a median of 3 cycles (range for both cohorts, 1-8). With a median follow-up of 7 months, the median survival for the FL cohort is 9.5 months (range, 0.6 - 11.1) and has not been reached for the R/R cohort (range, 0.6 - 13). Grade 3 or higher adverse events related to study drugs were mainly myelosuppression-related; 4 patients (11%) had infection complications, including 1 pt with life-threatening pneumonia, and 1 pt (3%) who had liver enzyme abnormality. Conclusion: ASTX727 and venetoclax combination is safe and feasible particularly in the advanced elderly population and demonstrates significant efficacy in pts unfit for chemotherapy both in the FL and R/R settings. Total oral therapy of ASTX727 and venetoclax combination appears to be a promising strategy for older and unfit patients with AML. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

In vitro and in silico inhibition performance of choline against CYP1A2, CYP2D6 and CYP3A4

Choline is an essential nutrient involved in the synthesis of acetylcholine in the cholinergic neurons. The pharmacokinetic properties of choline are well described; however, there is a lack of data about its activity toward the CYP450 superfamily of enzymes. Therefore, the aim of this study was to conduct in silico and in vitro activity assessments of choline against three major CYP450 isoforms—CYP1A2, CYP2D6, and CYP3A4. Preliminary in silico modeling was performed on a specialized DL-CYP Prediction Server to evaluate the affinity of choline toward the enzymes. The in vitro study contained specific cytochrome P450 isoform inhibitors and substrates (for CYP1A2, CYP2D6, and CYP3A4) to determine the inhibition performance of choline at five different concentrations (0.150 − 1 µmol/L). The potential interactions of choline and CYPs were displayed after molecular docking with Glide (Schrödinger). In addition, induced-fit simulations and binding free energy calculations MM/GBSA (Molecular Mechanics-Generalized Born Surface Area) were applied to predict the accessibility in each CYP isoform. The initial in silico simulations revealed that choline lacks inhibition potency against the aforementioned enzymes. The in vitro evaluations confirmed that choline possessed no effect against CYP1A2; however, at 1 µmol/L choline exerted 22% and 27% blocking capacity against CYP2D6 and CYP3A4, respectively. Furthermore, there was good correlation between the in vitro results and the complexes’ free binding energy recalculations. Overall, the assessments indicated that choline is a weak CYP2D6 and CYP3A4 inhibitor. The latter results should be considered as a source of future unwanted drug–drug interactions.

Synthesis, crystal structure and molecular docking study of novel isoxazole derivatives as CYP450 inhibitors in search of anticancer agents

Synthesis of some novel isoxazole derivatives and their molecular docking with enzymes from CYP450 family carried out using erlotinib, gemcitabine and ketoconazole as reference drugs are reported in this work. Eight isoxazole derivatives of 3,4-substituted phenyl 3-chloroacrylaldehyde and one isoxazole derivative of cinnamaldehyde were synthesized. A molecular docking study of all nine compounds shows good docking score compared to standard drugs erlotinib, gemcitabine and ketoconazole. 4-OH and 4-F derivatives were found to have strong affinity for all six CYP450 proteins under study in the present work. 4-F and 3-NO2 derivatives could be a suitable lead compound inhibitor to CYP1A2 followed by 4-OH derivatives. 4-OH derivative with significant binding affinity showed encouraging inhibition of CYP1A2, CYP2C9, CYP2C8, CYP2C19 and CYP2D6. The current predictions over these nine isoxazole derivatives of 3,4-substituted phenyl 3-chloroacrylaldehyde will be needed to be further investigated in vivo and in vitro conditions to identify the optimum therapeutic efficacy. Synthesis of the isoxazole derivatives is the first known report of the Knoevenagal condensation of acrylaldehyde derivatives to form isoxazole derivatives as per the literature survey. A detailed crystal structure study of five analogues gives insight into the solid-state structural features of this new framework with isoxazole moieties. Communicated by Ramaswamy H. Sarma

2,3,5,4′-Tetrahydroxy stilbene-2-Ο-β-D-glucoside, a mechanism-based inactivator of CYP2C19 and CYP3A4, potentiates hepatic protein adduction and hepatotoxicity induced by emodin in vivo

2,3,5,4′-Tetrahydroxy stilbene-2-Ο-β-D-glucoside (TSG) and emodin (EMD) are two main components of Polygonum multiflorum Thunb. (PMT). Its root is widely used as herbal medicine and supplement. However, PMT-induced liver injury has drawn increasing attention. The purpose of this study was to investigate the interaction of TSG with EMD in the aspects of enzymology, pharmacokinetics, and hepatotoxicity. Co-administration with TSG increased internal exposure of EMD, EMD-derived hepatic protein adduction, and EMD-induced liver injury in mice. Mouse and human liver microsomal incubation study demonstrated that co-incubation with TSG decreased the formation of hydroxylation metabolites of EMD. Human recombinant cytochrome P450 enzyme incubation study showed that TSG induced time-, concentration-, NADPH-dependent and irreversible inhibition of CYP2C19 and CYP3A4. An epoxide metabolite derived from TSG was responsible for the observed enzyme inactivations. The findings allow us to better understand the mechanisms by which herbal processing detoxifies raw PMT.

Evaluation of the Pharmacokinetic Drug Interaction of Capmatinib With Itraconazole and Rifampicin and Potential Impact on Renal Transporters in Healthy Subjects.

Capmatinib is a highly specific, potent, and selective mesenchymal-epithelial transition factor inhibitor predominantly eliminated by cytochrome P450 (CYP) 3A4 and aldehyde oxidase. Here, we investigated the effects of a strong CYP3A inhibitor (itraconazole) and a strong CYP3A inducer (rifampicin) on single-dose pharmacokinetics of capmatinib. In addition, serum creatinine and cystatin C were monitored to assess the potential inhibition of renal transporters by capmatinib. This was an open-label, 2-cohort (inhibition and induction), 2-period (capmatinib alone and inhibition/induction periods) study in healthy subjects. In the inhibition cohort, capmatinib (400 mg/day) was given alone, then with itraconazole (200 mg/day for 10 days, 5-day lead-in before coadministration). In the induction cohort, capmatinib (400 mg/day) was given alone, then with rifampicin (600 mg/day for 9 days, 5-day lead-in before coadministration). Fifty-three subjects (inhibition cohort, n = 27; induction cohort, n = 26) were enrolled. Coadministration of itraconazole resulted in an increase of capmatinib area under the plasma concentration-time curve from time 0 to infinity by 42% (geometric mean ratio [GMR], 1.42; 90%CI, 1.33-1.52) with no change in maximum plasma concentration (GMR, 1.03; 90%CI, 0.866-1.22). Coadministration of rifampicin resulted in a reduction of capmatinib area under the plasma concentration-time curve from time 0 to infinity by 66.5% (GMR, 0.335; 90%CI, 0.300-0.374) and a decrease in maximum plasma concentration by 55.9% (GMR, 0.441; 90%CI, 0.387-0.502). After a single dose of capmatinib, a transient increase in serum creatinine was observed with no change in serum cystatin C concentration during the 3-day monitoring period. In conclusion, coadministration of itraconazole or rifampicin resulted in clinically relevant changes in systemic exposure to capmatinib. The transient increase in serum creatinine without any increase in cystatin C suggests inhibition of renal transport by capmatinib.

ODP436 Adrenal Insufficiency After Combined Treatment of Itraconazole and Triamcinolone

Abstract Introduction Adrenal insufficiency (AI) has been reported due to the use of budesonide and itraconazole. We report an unusual presentation of adrenal insufficiency from the use of triamcinolone and itraconazole. Clinical Case 46-year-old man with a history of NASH and alcoholic cirrhosis requiring liver transplant presented to ER with two weeks of progressive lower extremity weakness. He reported difficulty climbing stairs and getting up from a chair. He denied anorexia, nausea, vomiting, abdominal pain, or lightheadedness. He was treated with itraconazole for diffuse histoplasmosis for over one year and received one dose of intra-articular triamcinolone 40mg for shoulder pain 2 weeks prior to the hospital admission. Physical exam was significant for proximal weakness, ecchymoses on upper and lower bilateral extremities, mild truncal obesity, but no violaceous striae, moon facies, dorsocervical fat pad or supraclavicular fullness. Laboratory evaluation was notable for sodium 129 mEq/L (n: 135-145), potassium 5.9 mEq/dl (n: 3.5-5), albumin 2.9 g/dl (n: 3.5-5) and glucose 345 mg/dl (n: 70-140), ACTH of 6 pg/ml (6-20) AM cortisol of &amp;lt;1 ug/dl (n: 4-20), aldosterone &amp;lt;1 ng/dl (n: 3-16), and plasma renin activity (PRA)20.54 ng/mL/h (n: 0.25-5.82). Serum cortisol increased to 3.4 ug/dl at 60 minutes of cosyntropin stimulation test, consistent with adrenal insufficiency. Synthetic glucocorticoid panel detected triamcinolone. Patient was discharged on hydrocortisone and fludrocortisone with marked clinical improvement. Abdominal MRI 3 months after admission did not show any adrenal involvement by histoplasmosis. Fludrocortisone was slowly titrated off and only hydrocortisone continued. Repeat evaluation 6 months after last triamcinolone injection demonstrated recovery of HPA axis with peak cosyntropin stimulation cortisol level 16.3 ug/dL (assay by Abbott Alinity) and recovery of renin/angiotensin/aldosterone axis (AM aldosterone 7 ng/dl, renin 2 ng/ml/h). Repeat synthetic glucocorticoid testing confirmed clearance of triamcinolone. Conclusion Itraconazole is CYP3A inhibitor that has been shown to decrease the metabolism and clearance of different corticosteroids. While our patient's lab results supported a diagnosis of AI, it was unclear if the etiology was primary (PAI) or central AI (CAI). The Na+, K+, aldosterone and PRA levels support a diagnosis of PAI; whereas the suppressed ACTH level supports CAI. We believe that our patient had an atypical presentation of both PAI due to histoplasmosis and CAI due to itraconazole/triamcinolone. This confounding picture can potentially be explained by an underlying PAI that may have been masked and exacerbated by the HPA axis suppression of the itraconazole/triamcinolone combination. Presentation: No date and time listed

ODP596 Central Adrenal Insufficiency After Intra-Articular Triamcinolone Injection In A Patient On Dolutegravir And Cobicistat Boosted Darunavir

Abstract Background Central adrenal insufficiency from drug-drug interaction between steroids and HIV anti-retroviral medications is a well-documented phenomenon in the literature, but in clinical practice making this diagnosis can prove challenging. Clinical Case 58-year-old woman with well-controlled HIV on dolutegravir and cobicistat/darunavir, type 2 diabetes mellitus, and chronic kidney disease presented to our emergency department with 3 days of polyuria, polydipsia, headaches, nausea, and decreased appetite. She also noticed that her glucose readings have been much higher than usual. 5 days prior to presentation, she received a 40 mg triamcinolone acetonide injection into her right subacromial bursa for chronic shoulder pain. For diabetes, she had been on the same dosage of weekly dulaglutide with good control. Initial laboratory evaluation revealed elevated serum glucose of 763 mg/dl (70 - 140 mg/dL) without an elevated anion gap, sodium of 124 mEq/L (135 - 145 mEq/L) and potassium of 5.9 mmol/L (3.6 - 5.2 mmol/L). Morning cortisol was sent as part of the workup for hyponatremia and returned low at 1.2 ug/dL (4 - 20 ug/dL). A 250 mcg cosyntropin stimulation test was performed, with baseline cortisol at 1.3 ug/dL and one-hour post-stimulation cortisol of 8.8 ug/dL. Pre-stimulation ACTH was &amp;lt; 5. 0 pg/mL (10 - 60 pg/mL). A synthetic glucocorticoid panel were sent on the 11th day after her injection and detected triamcinolone acetonide at 3.3 mcg/dL (cutoff: 0.1 mcg/dL) in urine and 0.85 mcg/dL (cutoff: 0.1 mcg/dL) in serum. She was diagnosed with iatrogenic adrenal insufficiency from intra-articular triamcinolone injection, the effect of which had been potentiated by her HIV medications cobicistat and dolutegravir (both CYP3A4 inhibitors). She was started on hydrocortisone and experienced improvement in appetite and fatigue. A plasma renin activity assay was elevated at 7.66 ng/mL/h (0.25 - 5.82 ng/ml/h) with 15 ng/dL of aldosterone (3 - 16 ng/dL). While awaiting the ACTH result, we discussed the possibility of primary adrenal insufficiency given persistent hyponatremia despite improved glucose control. However, given recent normal cross-sectional abdominal imaging, the history of steroid exposure, and lack of opportunistic infections in the past, central adrenal insufficiency remained the leading diagnosis. Further workup, including urine anion gap, eventually determined the cause of her hyponatremia to be a type 4 RTA likely related to her longstanding history of diabetes. The patient was discharged home on hydrocortisone with plan for repeat stimulation test in 6 weeks. Conclusion 1. Keep primary adrenal insufficiency in mind in a patient with HIV who presents with hyponatremia and low cortisol. 2. Steroid injections carry risks of significant hyperglycemia and iatrogenic adrenal insufficiency in patients receiving cobicistat and integrase inhibitor. Presentation: No date and time listed

PSAT052 Iatrogenic Cushing's Syndrome With a Remote History of Synthetic Glucocorticoid Use in the Setting of a CYP3A4 Inhibitor – Location Matters

Abstract Introduction The most common cause of Cushing's syndrome is iatrogenic due to the exogenous administration of glucocorticoids (GCs). Exogenous GCs disrupt the hypothalamic-pituitary-adrenal (HPA) axis by reducing ACTH production, thereby suppressing cortisol production by the adrenal gland. The degree of HPA axis suppression and recovery varies by the formulation, dose, duration, frequency, timing, and location of GC administration. It is also well known that the clearance of GCs is delayed by inhibitors of cytochrome P450 (CYP) 3A4 isoenzyme. Here we report a case in which a patient on cobicistat developed iatrogenic Cushing's syndrome (ICS) even with a remote history of GC use. Clinical Case A 34-year-old male with Human Immunodeficiency Virus (HIV) on cobicistat and a history of a motor vehicle accident was referred for evaluation of ICS. The patient was started on triamcinolone epidural injections after the accident and developed a ruddy face, weight gain, posterior neck fat redistribution, and purple abdominal striae. He received a total of nine injections over three months at an unknown dose with the last injection being given two years ago. His symptoms improved after stopping the regimen. He received no GCs again until four months prior to presentation when he completed a 4 mg methylprednisolone taper and the cushingoid phenotype returned. Biochemical workup was consistent with HPA axis suppression: morning cortisol &amp;lt;0.5 mcg/dL (4-22 mcg/dL), ACTH &amp;lt;5 pg/mL (6-50 pg/mL), and DHEAS 18 mcg/dL (106-464 mcg/dL). Synthetic glucocorticoid screen was positive for methylprednisolone 5.3 mcg/dL (n &amp;lt;0.10 mcg/dL) and triamcinolone 0.29 mcg/dL (n &amp;lt;0.1 mcg/dL). The patient denied any surreptitious GC use. We concluded the patient still had unmetabolized triamcinolone even after two years due to drug interactions from cobicistat, which is a CYP3A4 inhibitor. Moreover, epidural triamcinolone has the longest half-life, 523 hours, compared to oral or intraarticular injections. Clinical Lesson: GCs are primarily metabolized in the liver by CYP3A4. Very few cases have been reported with the use of cobicistat and the cushingoid phenotype typically appears within 3-6 months of the GC use. However, our patient had detectable triamcinolone and return of ICS two years after epidural injections. It is not enough to know whether a patient received GCs; it is also essential to know how it was given and the location of the injection as the half-lives vary depending on said location. This case reinforces the importance of pharmacovigilance and performing a thorough medication reconciliation, as even a remote history of steroid use in the setting of CYP3A4 inhibitors could lead to ICS. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.

Investigation of cytochrome P450 inhibitory properties of deoxyshikonin, a bioactive compound from Lithospermum erythrorhizon Sieb. et Zucc.

Deoxyshikonin, a natural naphthoquinone compound extracted from Lithospermum erythrorhizon Sieb. et Zucc (Boraginaceae), has a wide range of pharmacological activities, including anti-tumor, anti-bacterial and wound healing effects. However, the inhibitory effect of deoxyshikonin on cytochrome P450 (CYP) remains unclear. This study investigated the potential inhibitory effects of deoxyshikonin on CYP1A2, 2B1/6, 2C9/11, 2D1/6, 2E1 and 3A2/4 enzymes in human and rat liver microsomes (HLMs and RLMs) by the cocktail approach in vitro. The single-point inactivation experiment showed that deoxyshikonin presented no time-dependent inhibition on CYP activities in HLMs and RLMs. Enzyme inhibition kinetics indicated that in HLMs, deoxyshikonin was not only a competitive inhibitor of CYP1A2 and 2E1, but also a mixed inhibitor of CYP2B6, 2C9, 2D6 and 3A4, with Ki of 2.21, 1.78, 1.68, 0.20, 4.08 and 0.44 μM, respectively. In RLMs, deoxyshikonin not only competitively inhibited CYP2B1 and 2E1, but also exhibited mixed inhibition on CYP1A2, 2C11, 2D1 and 3A2, with Ki values of no more than 18.66 μM. In conclusion, due to the low Ki values of deoxythiokonin on CYP enzymes in HLMs, this may lead to drug-drug interactions (DDI) and potential toxicity.

Quantitation of Venetoclax in Human Plasma by High-Performance Liquid Chromatography with Ultraviolet Detection.

A simple, highly sensitive and specific method based on high-performance liquid chromatography (HPLC) with ultraviolet detection was developed for the measurement of venetoclax concentrations in plasma samples. The chromatographic method employed a mobile phase of acetonitrile: 0.5% KH2PO4 (pH3.5) (80/20, v/v) on a CAPCELL PAK C18 UG120 column at a flow rate of 0.5mL/min. The quantitative method was validated based on standards described in "Bioanalytical Method Validation: Guidance for Industry" published by the US Food and Drug Administration. The separation of venetoclax and the internal standard R051012 was satisfactory, and the chromatograms were free of interfering peaks from the biological matrix. The intra- and inter-day coefficients of variation for venetoclax assays were <12.9%, whereas intra- and inter-day accuracies were within 13.6%. Only 100μL of human plasma was required to detect a lower limit of quantification of 10ng/mL for venetoclax. The recoveries of venetoclax extracted with an Oasis HLB cartridge were between 81 and 85%. The developed HPLC method was successfully applied to the determination of venetoclax concentrations in plasma of acute myeloid leukemia patients taking venetoclax. The degree of drug interactions between venetoclax and CYP3A4 inhibitors can be determined by this HPLC assay.

Lumefantrine solid dispersions with piperine for the enhancement of solubility, bioavailability and anti-parasite activity

Crystallinity and P-glycoprotein (P-gp) mediated efflux of drugs with low aqueous solubility collaboratively contributes to erratic absorption resulting in low/variable bioavailability. Herein, the amorphous solid dispersions (SD) of lumefantrine (LUMF) containing piperine (PIP), a P-gp and CYP3A4 inhibitor, were formulated with Soluplus (Sol), Klucel (Klu) and Lutrol F68 (Lut), polymeric carriers, to improve solubility and bioavailability of LUMF following oral administration. The LUMF-PIP-SD prepared with Sol exhibited higher aqueous solubility of LUMF in concentration dependent manner and LUMF-PIP-Sol demonstrating maximum aqueous LUMF solubility were characterized by DSC, FTIR and XRD. The DSC thermogram and XRD diffractogram of LUMF-PIP-SD confirmed the loss of crystallinity of LUMF ensuing improved dissolution while possible interaction of LUMF with PIP and /or Sol was evident in FTIR spectrum. DSC and dissolution studies confirmed the stability for LUMF-PIP-Sol SD stored for 90 days under stressed conditions of humidity and temperature. An in situ single-pass intestinal perfusion study in rats indicated 2.2-fold increase in intestinal permeation of LUMF co-administered with PIP. Improved bioavailability of LUMF was evidenced by increased AUC0-∞ and Cmax for LUMF in SD compared to alone LUMF or LUMF with PIP. Peter’s four-day suppressive test indicated improved antimalarial activity for LUMF-PIP-Sol SD. Overall, the data suggest that the SD of LUMF incorporated with P-gp inhibitor PIP, improves the bioavailability as well as antimalarial efficacy of LUMF.

Effects of voriconazole and fluconazole on the pharmacokinetics of almonertinib in rats by UPLC-MS/MS.

Almonertinib was included in the first-line treatment of non-small cell lung cancer with EGFR T790M mutations by the Chinese Society of Clinical Oncology in 2021. Considering that immunocompromised lung cancer patients are prone to opportunistic fungal infections, and most triazole antifungal drugs are moderate or strong inhibitors of CYP3A4, this study was conducted to develop and validate an accurate and rapid ultra-performance liquid chromatography tandem mass spectrometry method for quantifying almonertinib in plasma and for investigating the pharmacokinetic changes of almonertinib caused by voriconazole and fluconazole in rats. After liquid-liquid extraction with tert-butyl methyl ether, an XSelect HSS T3 column (2.1 × 100 mm, 2.5μm, Waters) was used for the chromatographic separation of almonertinib and sorafenib-D3 (internal standard). The analytes were detected using an AB Sciex Triple Quad 5,500 mass spectrometer in the positive ionization mode. The method exhibited great linearity (0.5-200 ng/ml, r > 0.997) and stability under the established experimental conditions. All validation experiments were in accordance with the guidelines, and the results were all within the acceptable limits. This method was successfully applied to the researches of pharmacokinetics and drug interactions for almonertinib in rats. Voriconazole and fluconazole significantly altered the pharmacokinetic profiles of almonertinib and increased the systemic exposure of almonertinib in rats to different degrees, but further human trials should be conducted to validate the results.

New, Eco-Friendly Method for Synthesis of 3-Chlorophenyl and 1,1'-Biphenyl Piperazinylhexyl Trazodone Analogues with Dual 5-HT1A/5-HT7 Affinity and Its Antidepressant-like Activity.

Serotonin 5-HT1A and 5-HT7 receptors play an important role in the pathogenesis and pharmacotherapy of depression. Previously identified N-hexyl trazodone derivatives, 2-(6-(4-(3-chlorophenyl)piperazin-1-yl)hexyl)-[1,2,4]triazolo[4,3-a]pyridin-3(2H)-one hydrochloride (7a·HCl), with high affinity for 5-HT1AR and 2-(6-(4-([1,1'-biphenyl]-2-yl)piperazin-1-yl)hexyl)-[1,2,4]triazolo[4,3-a]pyridin-3(2H)-one hydrochloride (7b·HCl), a dual-acting 5-HT1A/5-HT7 receptor ligand, were prepared with a new microwave-assisted method. The protocol for the synthesis of 7a and 7b involved reductive alkylation under a mild reducing agent. We produced the final compounds with yield of 56-63% using ethanol or 51-56% in solvent-free conditions in 4 min. We then determined the 5-HT7R binding mode for compounds 7a and 7b using in silico methods and assessed the preliminary ADME and safety properties (hepatotoxicity and CYP3A4 inhibition) using in vitro methods for 7a·HCl and 7b·HCl. Furthermore, we evaluated antidepressant-like activity of the dual antagonist of 5-HT1A/5-HT7 receptors (7b·HCl) in the forced swim test (FST) in mice. The 5-HT1AR ligand (7a·HCl) with a much lower affinity for 5-HT7R compared to that of 7b·HCl was tested comparatively. Both compounds showed antidepressant activity, while 5-HT1A/5-HT7 double antagonist 7b·HCl showed a stronger and more specific response.