Prior Lines Of Systemic Therapy Research Articles

Erdafitinib (Balversa) for urothelial carcinoma.

Erdafitinib (Balversa – Janssen), an oral kinase inhibitor, has received full approval from the FDA for treatment of locally advanced or metastatic urothelial carcinoma in adults with susceptible FGFR3 (fibroblast growth factor receptor) genetic alterations who had disease progression on or after at least one prior line of systemic therapy.

Abstract PS12-06: A phase 2 study of abemaciclib monotherapy for patients with retinoblastoma-positive (Rb+), triple-negative metastatic breast cancer

Abstract Background: Cyclin-dependent kinase (CDK) 4/6 inhibitors can significantly extend survival when given in combination with endocrine therapy as treatment for hormone receptor-positive metastatic breast cancer. Preclinical studies suggest CDK4/6 inhibitor monotherapy might also be effective in a subset of triple-negative breast cancers (TNBCs), including those that express a functional retinoblastoma (RB) protein and/or those of the Luminal Androgen Receptor (LAR) subtype. Currently, the clinical activity of CDK4/6 inhibitor therapy in TNBC has not been reported. Methods: We conducted a single-arm phase II study of abemaciclib monotherapy in patients with locally advanced or metastatic TNBC. Key eligibility criteria included: (i) Measurable disease by RECIST 1.1; (ii) Between 1-3 prior lines of systemic therapy for advanced TNBC; (iii) RB-positive tumor (defined as ≥ 50% of tumor cells staining positive for RB by immunohistochemistry [archival or fresh sample] on central testing); (iv) ECOG PS 0/1. Patients were treated with abemaciclib 200 mg orally (28-day cycles) twice daily until disease progression, unacceptable toxicity, withdrawal of consent, or death. Tumor biopsies were mandatory at baseline and C2D1 if tumor tissue was safely accessible. The primary outcome was objective response rate (ORR). Key secondary endpoints included progression-free survival (PFS), overall survival (OS), clinical benefit rate (CBR: CR + PR + SD ≥ 24 weeks), and safety and tolerability. The study had a two-stage design. Thirteen patients were enrolled in the first stage, with the plan to enrol a further 25 patients if at least one objective response was observed. Results: One unconfirmed partial response was observed in stage 1, and a total of 27 patients were enrolled before the trial was closed early due to slow accrual. The median age was 61 years and patients had received a median of 2 prior lines of systemic therapy for metastatic disease. Twelve patients had received prior immunotherapy. After a median follow-up of 28.5 months, the confirmed ORR was 0% and the CBR was 15%, with 4 of 27 patients experiencing stable disease for ≥ 24 weeks. The median PFS was 1.94 months (95% CI: 1.8 – 11.5 months), and the median OS was 8.44 months (95% CI: 4.6 – 15.6 months). There was no significant difference in PFS or OS between patients with PD-L1-positive versus PD-L1-negative disease, or Androgen Receptor (AR) positive versus negative tumors by immunohistochemistry. The most common adverse events of grade 2 or higher were diarrhea (41%), neutropenia (41%), anemia (30%), and nausea (30%). RNA-sequencing of baseline biopsies has been performed to identify biomarkers associated with clinical benefit, and results will be presented at the meeting. Conclusions: Abemaciclib monotherapy did not show clinical activity in patients with Rb+ metastatic TNBC. This finding suggests that future trials of CDK4/6 inhibition as monotherapy in TNBC are not warranted. Citation Format: Shom Goel, Bojana Jovanović, Xiangying Chu, Melissa Hughes, Ayesha Mohammed-Abreu, Julie Kasparian, Timothy Erick, Molly DiLullo, Eileen Wrabel, Rinath Jeselsohn, Nabihah Tayob, Stuart Schnitt, Nancy Lin, Sara Tolaney. A phase 2 study of abemaciclib monotherapy for patients with retinoblastoma-positive (Rb+), triple-negative metastatic breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PS12-06.

Abstract PO5-16-12: EFFICACY AND TOLERABILITY OF METRONOMIC CHEMOTHERAPY (mChT) WITH CYCLOPHOSPHAMIDE, METHOTREXATE AND CAPECITABINE (CMX) IN PATIENTS WITH HEAVILY PRETREATED ADVANCED BREAST CANCER. RESULTS FROM A MULTICENTER RETROSPECTIVE STUDY

Abstract BACKGROUND mChT consists on the administration of repetitive, low doses of chemotherapy drugs and represents an attractive and active therapeutic strategy in cancer patients. Beyond the traditional cytotoxic effect of each drug on tumor cells, mChT seems to play a role in the modulation of angiogenesis and immune-regulation. mChT has demonstrated promising clinical activity and low toxicity in patients with advanced breast cancer (ABC). The aim of this study is to describe the safety and efficacy of CMX in a retrospective cohort of heavily pretreated HER2-negative ABC patients. METHODS This is a multicenter, retrospective study that included patients with HER2-negative ABC who received treatment with CMX (capecitabine 500 mg thrice daily, methotrexate 2.5 mg twice a week, and cyclophosphamide 50 mg daily). Demographic data, tumor characteristics, previous therapies, efficacy, and toxicity of the CMX treatment were collected. Statistical analyses were performed with Stata v.14. For standard summary statistics, mean and range for continuous data and relative and absolute frequencies for categorical data were used while for survival analysis Kaplan Meier approach was employed. RESULTS A total of 25 patients from 4 centers in Spain treated between October 2016 and February 2023 were included in this analysis. Median age was 63 years (range: 37-87), 68% had visceral disease, and 48% had triple-negative tumors. All patients previously received a median of 5 prior lines of systemic therapy in the metastatic setting and 80% of patients had been treated with capecitabine, most of them in the metastatic scenario with a median treatment duration of 6.2 months. Dose reductions were necessary in 5 patients and 1 patient discontinued treatment due to toxicity. No grade 3-4 hand-foot syndrome or diarrhea were reported. Objective response rate was 20.8% and disease control rate was 54.2%. Median progression-free survival was 6.1 months (95% confidence interval [CI] 95%; 4.3 - 12.4) and median overall survival was 12.3 months (95% CI; 6.8 - 24.7). Neither the number of previous lines of treatment nor the prior use of capecitabine showed a negative impact on the efficacy of CMX. CONCLUSIONS CMX is an effective and well-tolerated scheme of mChT and may represent an adequate treatment option for patients with heavily pretreated HER2-negative ABC, including those patients that previously received capecitabine as single agent. These encouraging data warrant further investigation. Citation Format: Cristina Saavedra, María Gion, Alfonso Cortés, Patricia Cortez, Laia Garrigós, José Manuel Pérez-García, Gabriele Antonarelli, Javier Cortés. EFFICACY AND TOLERABILITY OF METRONOMIC CHEMOTHERAPY (mChT) WITH CYCLOPHOSPHAMIDE, METHOTREXATE AND CAPECITABINE (CMX) IN PATIENTS WITH HEAVILY PRETREATED ADVANCED BREAST CANCER. RESULTS FROM A MULTICENTER RETROSPECTIVE STUDY [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-16-12.

Abstract PO2-19-08: INAVO121: Phase III study of inavolisib + fulvestrant vs alpelisib + fulvestrant in patients with hormone receptor-positive, HER2-negative, PIK3CA-mutated locally advanced or metastatic breast cancer

Abstract BACKGROUND Standard-of-care (SoC) endocrine therapy (ET) for patients (pts) with hormone receptor-positive, HER2-negative, PIK3CA-mutated locally advanced or metastatic breast cancer (HR+, HER2–, PIK3CA-mut LA/mBC) was transformed by combinations with cyclin-dependent kinase 4/6 inhibitors (CDK4/6is); a CDK4/6i-based combination is approved in high-risk early BC. However, in most pts, mechanisms of resistance that emerge during or after treatment with a CDK4/6i and ET combination lead to relapse/disease progression. Dysregulating mutations in PIK3CA, occurring in ~40% of HR+, HER2– BCs, represent a common mechanism of resistance to CDK4/6is and ET combinations. Alpelisib (ALP; a selective PI3Kα inhibitor; PI3Kαi) + fulvestrant (FUL) is approved for pts with HR+, HER2–, PIK3CA-mut LA/mBC, but its widespread implementation in clinical practice has been challenging. As such, there is a significant need to develop PI3Kαis with a better therapeutic index. Inavolisib (INAVO) is a highly potent and selective PI3Kαi that also facilitates the degradation of mutated PI3Kα isoform. INAVO has demonstrated manageable safety/tolerability, alone and in combination with SoC treatments in HR+, HER2–, PIK3CA-mut LA/mBC. Moreover, an ongoing Phase I trial showed that INAVO + FUL elicited encouraging preliminary antitumor activity in heavily pretreated pts, including a CDK4/6i-based regimen. TRIAL DESIGN INAVO121 is a Phase III, randomized, open-label study. Pts are randomized 1:1 to receive INAVO (9 mg oral daily; PO QD) + FUL (500 mg intramuscularly on Days [D] 1 and 15 of Cycle 1, then D1 of subsequent cycles), or ALP (300 mg PO QD) + FUL. Randomization is stratified by visceral disease (yes vs no) and prior CDK4/6i therapy (adjuvant vs metastatic setting). Pts will receive treatment until disease progression or unacceptable toxicity. ELIGIBILITY CRITERIA Pts have HR+, HER2–, PIK3CA-mut LA/mBC (confirmed by circulating-tumor DNA or tumor tissue), adequate hematologic and organ function, and disease progression after or during treatment with a CDK4/6i-based regimen. Up to two prior lines of systemic therapy in LA/mBC, including one line of chemotherapy, are allowed. AIMS The primary endpoint is progression-free survival (PFS) by blinded independent central review (BICR). Secondary endpoints include overall survival, BICR-objective response rate, BICR-best overall response, BICR-duration of response, BICR-clinical benefit rate, safety, tolerability, pt-reported outcomes, and pharmacokinetics. STATISTICAL METHODS A stratified log-rank test at an overall 0.05 significance level (two-sided) will be used for the primary endpoint analysis. Median PFS will be estimated using Kaplan–Meier methodology. An independent data monitoring committee will be in place for safety and efficacy. ACCRUAL The study is open for enrollment and has randomized four pts; the study is targeting 400 pts at ~200 sites globally. CONTACT INFORMATION For more information or to refer a patient, email global.rochegenentechtrials@roche.com or call 1-888-662-6728 (USA only). Clinicaltrials.gov number NCT05646862. This abstract was originally presented at ASCO 2023 (TPS1123). Citation Format: Dejan Juric, Kevin Kalinsky, Seock-Ah Im, Eva Ciruelos, Giampaolo Bianchini, Carlos Barrios, William Jacot, Peter Schmid, Sherene Loi, Hope Rugo, Veronica Craine, Katherine Hutchinson, Aulde Flechais, Eirini Thanopoulou, Nadia Harbeck. INAVO121: Phase III study of inavolisib + fulvestrant vs alpelisib + fulvestrant in patients with hormone receptor-positive, HER2-negative, PIK3CA-mutated locally advanced or metastatic breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-19-08.

Abstract PO4-06-07: Efficacy and safety of futibatinib in patients with locally advanced/metastatic triple-negative breast cancer harboring FGFR2 gene amplification: final results from the phase 2, open-label FOENIX-MBC2 study

Abstract Background: Triple-negative breast cancer (TNBC) accounts for ~15% of breast cancers and represents an aggressive subtype with limited targeted therapeutic options. Fibroblast growth factor receptor (FGFR) signaling plays an important role in breast tumorigenesis and metastasis. The phase 2 FOENIX-MBC2 study (NCT04024436) was designed to evaluate responses to futibatinib, a highly selective and potent irreversible covalent inhibitor of FGFR1–4 (FDA-approved for intrahepatic cholangiocarcinoma), in patients with metastatic breast cancer. Here, we report final efficacy and safety data for futibatinib in the cohort of patients with advanced/metastatic TNBC harboring FGFR2 gene amplification. Methods: Eligible patients had locally advanced/metastatic TNBC with measurable disease per RECIST v1.1, an ECOG performance status of 0/1, and progressive disease after ≥1 prior chemotherapy-containing regimen for advanced disease. Patients were positive for FGFR2 gene amplification determined by analysis of tumor tissue or circulating tumor DNA. Patients received oral futibatinib 20 mg once daily until disease progression, unacceptable toxicity, or other discontinuation criteria were met. The primary endpoint was objective response rate (ORR) by RECIST v1.1 in patients with centrally confirmed FGFR2 amplification. Responses (complete response and partial response) required confirmation after at least 4 weeks. Secondary endpoints included the 6-month progression-free survival (PFS) rate, PFS, duration of response (DOR), and overall safety. Results: Overall, 21 female patients with TNBC were enrolled (median age: 53 years) in this cohort. Patients had received a median 5 lines of prior systemic therapy. Overall, 2 patients had a confirmed partial response (ORR: 9.5%; 95% confidence interval [CI]: 1.2, 30.4), with a median DOR of 6.1 months (range: 3.1−9.2 months). Five (23.8%) patients had stable disease. PFS at 6 months was observed in 4 patients (19.0%; 95% CI: 5.4, 41.9) and the median PFS was 1.9 months (95% CI: 1.6, 4.0). Twenty patients (95.2%) had ≥1 treatment-related adverse event (TRAE), including 7 (33.3%) with a Grade 3 TRAE (no Grade 4 or 5). Common TRAEs (any grade) included hyperphosphatemia (85.7% of patients), constipation, diarrhea, fatigue, and dry skin (each in 23.8% of patients). Anemia was the only Grade 3 TRAE observed in more than 1 patient (n=2, 9.5%). Overall, 28.6% of patients had a serious adverse event (SAE; any cause), and 1 patient had an SAE leading to death (ischemic stroke). None of the SAEs or deaths were considered treatment-related. Conclusions: In heavily pretreated patients with metastatic TNBC harboring FGFR2 gene amplification, futibatinib monotherapy demonstrated modest anticancer activity. Futibatinib was tolerable and had an acceptable safety profile, consistent with previous data. Further biomarker work to identify patients who might benefit most from futibatinib is ongoing. Clinical trial information: NCT04024436 Citation Format: Antonio Giordano, Nisha Unni, Senthil Damodaran, Hope Rugo, Timothy Crook, Thomas Bachelot, Federico Piacentini, Hector Soto Parra, Ian Krop, Masashi Shimura, Gareth Tomlinson, Maciej Gil, Nicholas Turner, Fabrice André. Efficacy and safety of futibatinib in patients with locally advanced/metastatic triple-negative breast cancer harboring FGFR2 gene amplification: final results from the phase 2, open-label FOENIX-MBC2 study [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-06-07.

Abstract RF02-05: Report on Cohort Expansion of Phase I Study to Investigate the Safety, Tolerability, Pharmacokinetics and Antitumor Activity of BB-1701 in Patients with Locally Advanced/Metastatic HER2 Low Breast Cancer

Abstract Background: BB-1701 is an antibody-drug conjugate (ADC) consisting of a humanized IgG1κ monoclonal anti-HER2 antibody with the same sequence as trastuzumab and eribulin linked together by a cathepsin-cleavable valine-citrulline linker. Eribulin is an inhibitor of microtubule approved for the treatment of metastatic breast cancer and advanced liposarcoma, following prior therapies. When BB-1701 targets HER2 expressing cancer cells and it is internalized, free eribulin is cleaved from the ADC by cathepsin b and causes cytotoxicity to cancer cells. The neighboring cells were affected with bystander effects, like cytotoxicity on tumor cells and non-cytotoxic effects on microenvironment, by free eribulin released from dying cancer cells. Here, we report preliminary results from the ongoing cohort expansion of a phase I study of BB-1701 in patients with HER2 low breast cancer (ClinicalTrials.gov Identifier: NCT 04257110). Methods: Patients ≥ 18 years of age with confirmed locally advanced/metastatic HER2 low breast cancer (IHC 2+ and FISH negative or IHC 1+), that had progressed on at least two lines of prior standard therapies, with ECOG PS ≤ 2 and measurable disease (RECIST 1.1) were enrolled. HER2 expressions was determined by IHC and FISH before enrollment. Total of four dose levels of BB-1701 (1.0 mg/kg Q3W, 1.2 mg/kg Q3W, 1.4 mg/kg Q3W and 1.6 mg/kg Q3W) were administered during the cohort expansion. The safety, tolerability and preliminary anti-tumor activity of BB-1701 were assessed during study. Radiographic assessment was conducted every 6 weeks. Results: As of 30 June 2023, 40 patients with HER2 low breast cancer were enrolled in the four dose levels, 5 patients at 1.0 mg/kg Q3W, 20 patients at 1.2 mg/kg Q3W, 5 patients at 1.4 mg/kg Q3W and 10 patients at 1.6 mg/kg Q3W. Median age was 55 years (range 30-74), 97.5% were female, and 30.0%/70.0% patients were ECOG PS 0/1. The median prior lines of systemic therapy were 3 (range 2 – 9). All subjects experienced at least one treatment emergent adverse events and treatment-related adverse events (TRAEs) occurred in 30 subjects. The most common all grade TRAEs (≥20%) were peripheral neuropathy, aspartate aminotransferase increased, alanine aminotransferase increased, anemia, white blood cell count decreased. Grade 3 TRAEs were peripheral neuropathy (3 subjects), peripheral sensory neuropathy (2 subjects), neutrophil count decreased (2 subjects), platelet count decreased (1 subject), white blood cell count decreased (1 subject). There were no grade 4 or grade 5 events. The treatment related serious adverse events (SAEs) were peripheral sensory neuropathy (1 subject) and infusion related reaction (1 subject). There was no interstitial lung disease reported. No patients discontinued the study treatment due to AE. Of the 40 patients enrolled, 38 patients were evaluable for antitumor activity. At 1.0 mg/kg dose level, of 5 patients treated, 2 achieved partial response (PR), 2 had stable disease (SD), best overall response rate (BOR) was 40.0% (2/5) and disease control rate (DCR) was 80.0% (4/5). At 1.2 mg/kg dose level, of 18 patients treated, 5 achieved PR, 11 had SD with BOR of 27.8% (5/18) and DCR of 88.9% (16/18). At 1.4 mg/kg dose level, of 5 patients treated, 2 achieved PR, 2 had SD with BOR of 40.0% (2/5), and DCR was 80.0% (4/5). One patient who achieved PR was previously progressed on sacituzumab govitecan. At 1.6 mg/kg dose level, of 10 patients treated, 1 achieved CR, 3 achieved PR, 2 had SD with BOR of 40.0% (4/10), and DCR of 60.0% (6/10). Among these patients, the patient who achieved CR was previously treated by disitamab vedotin, and one patient who achieved PR was previously treated by trastuzumab deruxtecan. Conclusions: BB-1701 has demonstrated promising preliminary antitumor activity in HER2 low breast cancer including patients who received prior anti-HER2 ADCs, and a manageable safety profile. Citation Format: Fei Ma, Pamela Munster, Xiaoxiang Guan, Jingfen Wang, Herui Yao, Erika Hamilton, Xian Wang, Yehui Shi, Xinjun Liang, Nong Xu, Huoling Tang, Yuhong Zhou, Ziping Wei. Report on Cohort Expansion of Phase I Study to Investigate the Safety, Tolerability, Pharmacokinetics and Antitumor Activity of BB-1701 in Patients with Locally Advanced/Metastatic HER2 Low Breast Cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr RF02-05.

Abemaciclib plus endocrine therapy versus chemotherapy after progression on prior palbociclib in HR+/HER2- metastatic breast cancer: A single center real-world study in China.

Cyclin-dependent kinase (CDK) 4/6 inhibitor plus endocrine therapy (ET) become standard-of-care for patients with hormone receptor-positive, human epidermal growth factor receptor-2 negative (HR+/HER2-) metastatic breast cancer (MBC). However, the optimal therapeutic paradigm after progression on CDK4/6 inhibitor remains unclear. This study aimed to evaluate the efficacy and safety of abemaciclib with switching ET versus chemotherapy after progression on prior palbociclib-based ET in Chinese patients with HR+/HER2- MBC. From 414 consecutive patients with HR+/HER2- MBC who had been treated with palbociclib plus ET from September 2018 to May 2022 in Peking University Cancer Hospital, we identified 80 patients who received abemaciclib plus switching ET or chemotherapy after progression on palbociclib, matched for age, original stage at diagnosis, disease-free interval, and tumor burden at 1:1 ratio. The primary endpoint was progression-free survival (PFS) compared using the Kaplan-Meier method. A Cox proportional hazard model was performed to identify clinical factors associated with PFS in the abemaciclib group. The median PFS was 6.0 months (95% confidence interval [CI]: 3.94-8.06) in abemaciclib group and 4.0 months (95% CI, 2.52-5.49) in chemotherapy group (p = 0.667). And, there was no difference in median PFS between the sequential and nonsequential arm (6.0 vs. 6.0 months) in the abemaciclib group though fewer lines of prior systemic therapy and longer PFS from prior palbociclib in the sequential arm. However, patients with prior palbociclib as the first-line therapy had a significantly longer median PFS versus prior palbociclib as ≥2nd-line therapy (11.0 vs. 5.0 months, p = 0.043). Based on multivariable analysis, ER+/PR+ was an independent factor associated with longer PFS. There was no significant difference in overall survival between the abemaciclib and chemotherapy groups (p = 0.069). Our findings indicate that abemaciclib plus switching ET might be one of feasible treatment options for Chinese patients with HR+/HER2- MBC after progression on prior palbociclib-based therapy in addition to chemotherapy.

Belumosudil (Rezurock)

CADTH reimbursement reviews are comprehensive assessments of the clinical effectiveness and cost-effectiveness, as well as patient and clinician perspectives, of a drug or drug class. The assessments inform non-binding recommendations that help guide the reimbursement decisions of Canada’s federal, provincial, and territorial governments, with the exception of Quebec. This review assesses belumosudil (Rezurock), 200 mg oral tablets once daily. Indication: For the treatment of adult and pediatric patients 12 years and older with chronic graft-versus-host disease after failure of at least 2 prior lines of systemic therapy.

Abstract CT182: Oncolytic virus CF33-hNIS for the treatment of advanced cancer

Abstract Background: CF33-hNIS is a novel vaccinia virus engineered with the human sodium-iodide symporter (hNIS) gene. CF33-hNIS selectively replicates in tumor cells and promotes anti-tumor immunity. Here, we report results on a first-in-human phase 1 dose escalation study of CF33-hNIS, administered intratumorally (IT) or intravenously (IV) in adult patients with metastatic or advanced solid tumors (MAST). Methods: The MAST study is evaluating the safety of CF33-hNIS administered IT or IV, alone or in combination with pembrolizumab in patients with advanced or metastatic solid tumors with ≥ 2 prior lines of therapy (NCT05346484). CF33-hNIS is administered in 21-day cycles on C1D1 and C1D8, then D1 of each cycle thereafter. Pembrolizumab begins C2D1 for the combination groups and is administered Q3W. The study consists of two parts. Part 1 follows a 3+3 dose escalation scheme independent of each route of CF33-hNIS administration (IT and IV) and for each therapy regimen (monotherapy and combination therapy) with up to 7 dose levels of CF33-hNIS ranging from 8.6x105 to 3.0x109 PFU. Part 2 is a cohort expansion in select indications at the optimal dose. The co-primary endpoints are safety and identification of the recommended phase 2 dose. Secondary endpoints include objective response rate according to RECIST v1.1 and iRECIST, and assessment of viral replication in tumor lesions via Single-Photon Emission Computerized Tomography (SPECT). Results: As of Dec 2023, 36 patients have been treated in Part 1 of the study with a median age of 59 (range 23-81). Twenty-two (61%) patients were heavily pretreated with ≥3 prior lines of systemic therapy, and 14 (39%) received prior treatment with checkpoint blockade. Treatment-related adverse events consisted predominantly of ‘flu-like’ symptoms, such as grade 1/2: fatigue (31%), pyrexia (22%), and chills (14%). No dose-limiting toxicities have occurred. The highest dose treated to date is 1.1x108 PFU by IT and IV delivery; dose escalation continues. In the IT cohorts (14 patients), 7 of 15 (47%) injected lesions had a reduction in tumor burden, three lesions were completely eradicated. Three patients (21%) had an objective response: one complete response by iRECIST in a patient with cholangiocarcinoma; and two partial responses in patients with melanoma by RECIST. In IV cohorts (17 patients), 53% of patients achieved stable disease as their best response. Patients who received prior checkpoint blockade therapy derived clinical benefit with and without pembrolizumab. Viral replication, assessed by SPECT was higher in patients that saw a reduction in tumor burden. Immunological changes in peripheral blood and tumor biopsies will be presented. Conclusions: CF33-hNIS alone or in combination with pembrolizumab is a safe treatment option for advanced cancer patients. Encouraging efficacy has warranted advancement to part 2 of this study with a cohort expansion of patients with cholangiocarcinoma and other tumor types. Citation Format: Daneng Li, Anthony F. Shields, Hirva Mamdani, Patrick Travis, Gavin Wright, Wallace Akerley, Alex Spira, Gregory Daniels, Jaime Merchan, Abhijeet Kumar, Emerson Lim, Colt Egelston, Oscar Flores, Stanley Hamilton, Janet Austria, Amanda Seiz, Sharon Yavrom, Seymour Fein, John Byon, Paul Woodard, Grey A. Wilkinson, Jennifer Leddon. Oncolytic virus CF33-hNIS for the treatment of advanced cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT182.

Abstract CT109: Livmoniplimab and budigalimab combination therapy in treating patients with metastatic ovarian granulosa cell tumors: Results from dose escalation in a first-in-human study

Abstract Background: Ovarian granulosa cell tumors (OGC) are rare, accounting for 5-7% of all ovarian cancers and fatal when metastatic. There are no approved targeted therapies for metastatic OGC. Several agents with different targets, such as pembrolizumab, nirogacestat, orteronel, and STM 434, are being evaluated but to date have not shown clinical benefit. Most OGC carry a C134W mutation in the FOXL2 gene, which manifests its protumor effects via the transforming growth factor (TGF)-β signaling pathway. Livmoniplimab (livmo) is a monoclonal antibody (mAb) that specifically binds to the TGF-β1-glycoprotein-A repetitions predominant protein complex, blocking the release of active TGF-β1. Livmo has been assessed with or without budigalimab (budi), an anti-PD-1 mAb, in the dose escalation (ESC) part of a first-in-human study in patients (pts) with advanced solid tumors, including OGC. Herein, we report results of 4 pts with OGC enrolled into the combination ESC part of this phase 1 study (NCT03821935). Methods: Pts ≥18 years with ECOG PS 0-1 were enrolled in ESC, including pts with metastatic OGC refractory to/not eligible for standard therapies. The maximum tolerated dose was not reached, and pts received the maximum administered dose of 1500 mg livmo (Q2W IV) + 500 mg budi (Q4W IV). Safety and overall response rate (ORR) per RECIST v1.1 were assessed. Results: As of 28 Sep 2023, 57 pts were enrolled in ESC, including 4 with metastatic OGC aged 50-63 years who received 3-7 prior lines of systemic therapy. In total, 98% (n=56) pts in ESC experienced TEAEs, most commonly fatigue (42%), nausea (37%), and anemia (37%). One pt with OGC was enrolled in the study with metastatic target lesions in the lung, liver, and peritoneum at screening. She had received 7 prior lines of therapy including doxorubicin, bevacizumab, anastrozole, tamoxifen, and carboplatin + paclitaxel. Upon treatment with livmo + budi, she had a deep partial response (-92% from baseline) and a complete response in the target liver lesion. The pt stayed in response for ~2.5 years before death due to an event unrelated to study drugs. Furthermore, 2 other pts with metastatic OGC had a partial response (ORR=75%) and none of the 4 pts with OGC experienced disease progression (disease control rate=100%). Conclusions: Livmo + budi had promising antitumor efficacy and a tolerable safety profile in pts with metastatic OGC, a rare TGF-β signaling-dependent tumor. All enrolled pts with OGC showed tumor shrinkage and 1 pt had durable and near-complete response. Since single-agent pembrolizumab exhibited an ORR of 0% in pts with OGC (How et al. Invest New Drugs, 2021;39:829-835), we conclude that OGC is a proof-of-mechanism indication for livmo and that targeting TGF-β may represent an effective strategy for treating pts with OGC. Citation Format: Ildefonso Rodriguez Rivera, David Sommerhalder, Mohammad Sahtout, Cristiano Ferlini, Duyen Ngo, Sujata Jha, John Engelhardt, Anthony Tolcher. Livmoniplimab and budigalimab combination therapy in treating patients with metastatic ovarian granulosa cell tumors: Results from dose escalation in a first-in-human study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT109.

Abstract CT037: A phase I investigator-initiated trial of evorpacept (ALX148), lenalidomide and rituximab for patients with relapsed or refractory B-cell non-Hodgkin lymphoma

Abstract Introduction. We have recently demonstrated that pro-tumoral SIRPα+ macrophages may mediate resistance to lenalidomide and rituximab (R2) in patients (pts) with relapsed or refractory (RR) B-cell non-Hodgkin lymphoma (B-NHL). Evorpacept (ALX148) is a novel high-affinity CD47 blocker that abrogates the ‘do-not-eat-me signal’ provided to SIRPα+ macrophages. In a phase I trial including 33 pts with RR B-NHL it was well tolerated in combination with rituximab. We hypothesized that evorpacept and R2 will be synergistic, and the combination will be safe and effective for the treatment of pts with RR B-NHL. Methods. This single arm phase I study (NCT05025800) was conducted between 11/2021 and 9/2023 (data cut-off 12/2023). Adult pts with RR B-NHL who had received at least 2 prior lines of systemic therapy (1 in case of indolent B-NHL [iNHL]) were included. Evorpacept was administered intravenously (IV), in a 28-day cycle, for 12 cycles, at two dose levels (DL): 30 mg/Kg on day (D) 1 and D15 (DL1), or 60 mg/Kg on day 1 (DL2); rituximab IV was given weekly during cycle 1, and on D1 during cycles 2-6; lenalidomide was given orally on D1-21 during cycles 1-6. Dose limiting toxicity (DLT) was evaluated according to CTCAE v5 during cycle 1 and a Bayesian Optimal Interval design was used, with a target DLT rate of 0.3. Response was assessed according to Lugano 2014 criteria. Results. Twenty pts were included in the study. Median age was 61 (27-85), 10 (50%) were male, and 7 (35%) were non-white; 15 (75%) had follicular lymphoma, 3 (15%) marginal zone lymphoma, 1 (5%) mantle cell lymphoma, and 1 (5%) Richter Syndrome; 20 (100%) had previously received an anti-CD20 monoclonal antibody, 13 (72%) chemoimmunotherapy, and 15/18 (83%) iNHL pts had intermediate-high FLIPI. Three pts were treated at DL1, 17 at DL2, and no DLT was observed. The most common grade 3-4 adverse events included: neutropenia (55%), infections (30%), ALT increase (15%), AST increase (10%), skin rash (10%), and anemia (10%). Eight (40%) pts experienced a cycle delay, mainly due to grade (G) 1 AST/ALT elevation; 6 (30%) required a dose reduction for lenalidomide, none for evorpacept; 1 pt discontinued treatment after 1 cycle due to G3 lenalidomide-associated myocarditis. Sixteen (80%) pts achieved CR and best overall response rate was 90%. After a median follow-up of 16 months (95% CI, 12-20 months), 1-year PFS rate was 70% and 1-year OS rate was 90%. Conclusions. The combination of evorpacept and R2 is well tolerated in pts with RR B-NHL, with similar toxicity and promising anti-tumoral activity as compared to historical CR rates with R2 alone (34%). Bulk RNA sequencing and multiplex immunofluorescence are being performed on tissue biopsies collected before and during treatment, to characterize its effects on the tumor immune microenvironment. A phase 2 study investigating its efficacy in pts with previously untreated iNHL is now enrolling. Citation Format: Paolo Strati, Lei Feng, Dai Chihara, Jason Westin, Sairah Ahmed, Luis Fayad, Jared Henderson, Jeffrey Davidson, Elizabeth McChesney, Loretta Nastoupil, Sattva Neelapu, Christopher Flowers. A phase I investigator-initiated trial of evorpacept (ALX148), lenalidomide and rituximab for patients with relapsed or refractory B-cell non-Hodgkin lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT037.

Cost-Effectiveness of Axicabtagene Ciloleucel for Adult Patients With Relapsed or Refractory Follicular Lymphoma in the United States

ObjectivesThe results of a recent single-arm trial (ZUMA-5) of axicabtagene ciloleucel (axi-cel) for relapsed/refractory (r/r) follicular lymphoma (FL) demonstrated high rates of durable response and tolerable toxicity among treated patients. To quantify the value of axi-cel compared with standard of care (SOC) to manage r/r FL patients who have had at least 2 prior lines of systemic therapy (3L+), a cost-effectiveness model was developed from a US third-party payer perspective. MethodsA 3-state partitioned-survival cost-effectiveness model was developed with a lifetime horizon. Patient-level analyses of the 36-month ZUMA-5 (axi-cel) and SCHOLAR-5 (SOC) studies were used to extrapolate progression-free and overall survivals. After 5 years of survival, an estimated 40% of the modeled population was assumed to experience long-term remission based on literature. Results include the incremental cost-effectiveness ratio (ICER) measured as incremental cost per quality-adjusted life year (QALY) gained. One-way sensitivity analysis, probabilistic sensitivity analysis, and scenario analyses were performed. All outcomes were discounted 3% per year. ResultsAxi-cel led to an increase of 4.28 life-years, 3.64 QALYs, and a total cost increase of $321 192 relative to SOC, resulting in an ICER of $88 300 per QALY. Across all parameters varied in the one-way sensitivity analysis, the ICER varied between $133 030 and $67 277. In the probabilistic sensitivity analysis, axi-cel had a 99% probability of being cost-effective across 5000 iterations using a $150 000 willingness-to-pay threshold. ConclusionsGiven the robustness of the model results and sensitivity analyses, axi-cel is expected to be a cost-effective treatment in 3L+ r/r FL.

Phase II study of pembrolizumab and lenvatinib in advanced well-differentiated neuroendocrine tumors

Immune checkpoint inhibitors (CPIs) have not been shown to be active in well-differentiated neuroendocrine tumors (NETs), with response rates <5%. Lenvatinib is a multitargeted tyrosine kinase inhibitor which binds to vascular endothelial growth factor and fibroblast growth factor receptors and has demonstrated efficacy in pancreatic and gastrointestinal NETs [44% and 16% objective radiographic response rate (ORR), respectively]. The combination of antiangiogenic and CPI therapies can be synergistic. We therefore evaluated the combination of lenvatinib and pembrolizumab in well-differentiated gastrointestinal (GI) and thoracic NETs. A prospective, phase II trial evaluated patients with advanced GI/thoracic NETs (pancreatic NETs were excluded due to high response rate of lenvatinib monotherapy in this patient population), with evidence of progression within 8 months of study entry and at least two prior lines of systemic therapy. Patients received lenvatinib 20 mg daily and pembrolizumab 200 mg intravenously every 3 weeks until unacceptable toxicity or progression of disease. Primary endpoint was objective response rate, and an interim analysis was planned once 20 patients were enrolled. Four ORRs were required to continue enrollment. Twenty patients were enrolled on protocol from April 2021 to January 2022 (nine small intestine, five lung, two thymic, two unknown primary, one cecal, one presacral primaries). Two patients (10%) achieved a partial response (atypical lung and small intestinal primaries). Median progression-free survival (PFS) was 8 months (95% confidence interval 5.8-10.2 months). Twelve (60%) patients experienced probably or definitely associated grade 3 adverse events (10 hypertension). Fourteen patients (70%) required dose reductions or discontinued one of the medications. Two patients discontinued treatment before radiographic assessment. The combination of pembrolizumab and lenvatinib did not show sufficient response in patients with NETs to warrant continued enrollment on trial.

Belumosudil (Rezurock)

&#x0D; CADTH recommends that Rezurock be reimbursed by public drug plans for the treatment of chronic graft-versus-host disease (cGVHD) if certain conditions are met.&#x0D; Rezurock should only be covered to treat patients aged 12 years and older who have clinically diagnosed moderate to severe cGVHD and whose disease has not shown an adequate response to at least 2 prior lines of systemic therapy (1 of which is corticosteroids with or without calcineurin inhibitors).&#x0D; Rezurock should only be reimbursed if prescribed by clinicians who have experience in the diagnosis and management of patients with cGVHD, and the cost of Rezurock is reduced.&#x0D;

Cabozantinib plus atezolizumab in locally advanced/metastatic adrenocortical carcinoma: Results from a multi-cohort basket phase II trial, CABATEN/GETNE-T1914.

1 Background: Adrenocortical carcinoma (ACC) is a rare malignancy with a poor prognosis and limited therapeutic options. Immunotherapy and targeted therapy showed limited activity as single therapeutic strategies in ACC but synergism has been observed when combined in other genitourinary tumors such as Prostate and renal cell cancers. Therefore, we evaluated the activity and safety of cabozantinib plus atezolizumab in advanced/metastatic ACC. Methods: CABATEN was a prospective, multi-center, open-label, phase II study including patients with advanced and refractory endocrine and neuroendocrine tumors in 6 independent cohorts. Patients with locally advanced / metastatic ACC, ≥18 years old and ECOG 0-1 were included after progression to chemotherapy and/or mitotane. Prior treatment with cabozantinib or any immune checkpoint inhibitors was not allowed. Patients received atezolizumab 1200 mg IV Q3W plus cabozantinib 40 mg/day PO until progression or unacceptable toxicity. The primary endpoint was Objective Response Rate (ORR) by RECIST 1.1. Secondary endpoints included progression-free survival (PFS), overall survival (OS), and safety. The study empowered a Simon II stage design, requiring 1 response out of 9 patients at 1st stage to continue accrual in a 2nd stage, for a total of 24 patients. Three responses out of the 24 patients were required in the 2nd stage to consider the study positive for the cohort. Results: From October 2020 to November 2022, 24 patients with ACC were included, 54.2% were female and the median age was 51 years. Most (87.5%) were metastatic at inclusion, 45.8% were functioning, and 20.8% presented hypercortisolism. Most patients (54.2%) had ≥ 2 prior lines of systemic therapy for advanced disease (chemotherapy 91.7%, mitotane 45.8%). Cabozantinib was administered for a median of 3 months (95% CI: 2.7-6.1) and required reduction to 20 mg/day in 20.8% of patients. Atezolizumab was administered for a median of 4.5 cycles (95% CI: 4-8). Treatment was discontinued mainly due to disease progression (79.2%). Treatment discontinuation due to toxicity occurred in 9 (9.7%) patients. The ORR was 8.3% (95% CI: 1-27), including two partial responses that lasted for 5.4 and 17.4 months respectively. After a median follow-up of 10.7 months (range: 2.1-25.7), the median PFS was 2.9 months (95% CI: 2.8-5.7) and the median OS was 13.5 months (95% CI: 8.8-NR). Treatment-related adverse events (grade ≥3) were observed in 20.8% of the patients, consisting of hypertension (12.5%), and transaminase increase (8.3%). Conclusions: Cabozantinib plus atezolizumab showed modest activity in locally advanced/metastatic ACC. Safety profile was consistent with previous reports. The existence of long lasting responders makes it worthwhile to continue investigating predictive factors that help select patients for this combination. Clinical trial information: EudraCT:2019-002279-32 / NCT04400474 .

Phase 1/2 study of monalizumab plus durvalumab in patients with advanced solid tumors

BackgroundThe combination of monalizumab (anti-NKG2A/CD94) and durvalumab (anti-programmed death ligand-1) may promote antitumor immunity by targeting innate and adaptive immunity. This phase 1/2 study of monalizumab and durvalumab evaluated safety,...

A multi-center retrospective cohort study of patients with mCRPC who received lutetium Lu177 vipivotide tetraxetan.

89 Background: Lu177-vipivotide tetraxetan (Pluvicto) (Lu177-Plu) is the first FDA approved theragnostic for mCRPC. Since FDA approval in March 2022, there have been no published multicenter evaluations of real-world experiences with Lu177-Plu in the United States (US). We therefore present data from 2 academic centers on patient (pt) characteristics, treatment patterns and outcomes for mCRPC pts receiving SOC Lu177-Plu. Methods: Retrospective data was aggregated from University of Chicago &amp; Vanderbilt University on pt demographics, disease course and treatment for mCRPC pts who received SOC Lu177-Plu between 6/1/2022 and 9/1/2023. Research was conducted under IRBs VU211334 and IRB23-0718. 146 pts were identified who completed Lu177-Plu treatment by data cutoff 9/1/2023; their data is reported here. Results: Median age at cycle 1 (C1) was 72 years (range 49-93). Self-reported race was Black (23%), White (65%), Other/Unknown (UNK) (12%). Mean distance from home to treatment center was 79 mi. (range 1-1,317); 37% travelled &gt; 50 mi. At diagnosis, Gleason score was &gt;8 in 57%; 55% had locoregional disease, 44% had metastases, 1% were UNK. Median lines of prior systemic therapy were 4 (range 1-6), 95% received prior taxane(s) and 100% received prior androgen receptor signaling inhibitor (ARSI); 67% received 2 prior ARSI classes. PSMA-PET scan reported disease in bone in 93% of pts, lymph node 63%, liver 14%, lung 6%, other 25% (mostly prostate &amp; soft tissue). While undergoing 177Lu-Plu, 10% received concurrent ARSI (n=9 abiraterone, n=6 enzalutamide). Median cycles received was 3.5. 27 pts (18%) discontinued after C1, 46 (32%) after C2/3, 24 (16%) after C4/5 and 49 (34%) completed 6 cycles. 38% had a PSA &gt; 50% decline on treatment. 71 pts (49%) got scans between C1 and C6. Reasons cited for discontinuation prior to 6 cycles (n=97) included: progressive disease (including radiographic and/or PSA progression) (31%), progressive disease and toxicity (13%), toxicity (30%), clinical decline (including ECOG PS, transition to hospice or death) (23%), other (3%). 36 pts (25%) required supportive care with blood products (n=35 RBC, n=2 platelets). At data cutoff, 73 of 146 pts were alive (confirmed (n=66), unconfirmed (n=7)). Of deceased patients, median survival from C1 to death was 4.8 months (range 0.4-11.7). Conclusions: To our knowledge, this is the largest multicenter retrospective analysis of a racially diverse cohort of mCRPC pts receiving SOC Lu177-Plu following FDA approval in the US. PSA decline, median number of cycles received, fraction not requiring blood products in this cohort were all lower than in the VISION trial, likely due to baseline pt characteristics and potentially more liberal pt selection. Our data highlights numerous areas of need: expanded geographic access, optimized pt selection, standardization of scan type and interval on therapy and further data on concurrent therapy.

Addition of metastasis-directed therapy to standard-of-care systemic therapy for oligometastatic pancreatic ductal adenocarcinoma (EXTEND): Results of a multicenter, randomized phase II trial.

603 Background: Standard treatment of oligometastatic pancreatic ductal adenocarcinoma (PDAC) consists of multi-agent chemotherapy, although outcomes remain poor. We tested the hypothesis that the addition of comprehensive metastasis-directed therapy (MDT) to standard-of-care systemic therapy would improve progression-free survival (PFS) compared with systemic therapy alone. Methods: The External Beam Radiation to Eliminate Nominal Metastatic Disease (EXTEND) trial is a multicenter phase II basket trial randomizing patients with ≤ 5 solid tumor metastases 1:1 to MDT plus systemic therapy versus systemic therapy alone. Each histology-specific basket was pre-specified and independently powered for the primary endpoint of PFS; here we present results of the pancreatic cancer basket. Progression was defined by radiographic criteria (RECIST v1.1), clinical events, or death. Patients were stratified at randomization by number of metastases (1-2 vs 3-5), number of prior lines of systemic therapy (0-1 vs 2+), and cancer antigen 19-9 (CA-19-9) level (&lt;90U/ml vs ≥90U/ml). Exploratory endpoints included systemic immune response measures. The cutoff date for the primary analysis was September 1, 2023. ClinicalTrials.gov registration: NCT03599765. Results: Between March 2019 and February 2023, 41 patients with oligometastatic PDAC were randomized and 40 were eligible for PFS analysis (MDT arm: 19 patients; control arm: 21 patients). Baseline characteristics were well-balanced between arms. Thirty-one patients experienced progression or death; median follow-up time for censored patients was 9.9 months. The MDT arm had significantly longer PFS compared to the systemic therapy arm (median PFS 10.3 versus 2.5 months; log-rank p=0.006). After stratification, the estimated PFS hazard ratio was 0.43 (95% confidence interval: 0.20, 0.94; p=0.03) for MDT compared with systemic therapy. There were no grade 3 or greater adverse events with at least possible attribution to MDT, and only one grade 2 adverse event possibly related to treatment in the MDT arm occurred. Increased systemic T-cell stimulatory cytokines, CD8+ T-cell activation, CD8+ T-cell proliferation, and T-cell receptor clonal expansion following treatment were associated with the MDT arm compared with the control arm (all p&lt;0.05). Conclusions: Among patients with oligometastatic PDAC, the combination of MDT plus systemic therapy was associated with improved PFS compared with systemic therapy alone. Further exploration in phase III trials is warranted, as is investigation into the potential therapeutic implications of systemic immune activation associated with MDT receipt. Clinical trial information: NCT03599765 .

An open-label, multicenter study investigating RP3 oncolytic immunotherapy in combination with first- or second-line systemic atezolizumab plus bevacizumab in patients with locally advanced unresectable or metastatic hepatocellular carcinoma.

TPS576 Background: Despite advances in treatment for unresectable hepatocellular carcinoma (HCC), long-term survival rates remain poor. The combination of atezolizumab (Atezo) plus bevacizumab (Bev) is approved frontline therapy for advanced HCC, but a minority of patients (pts) respond and secondary resistance usually occurs within months. HCC has an immune-suppressed tumor microenvironment (TME), mediated by activated immune checkpoint signaling and angiogenesis pathways, which may contribute to therapeutic resistance. RP3 is a genetically modified herpes simplex virus type 1 (HSV-1) that expresses the fusogenic gibbon ape leukemia virus glycoprotein with the R sequence deleted (GALV-GP-R–), an anti–CTLA-4 antibody-like molecule, CD40 ligand, and 4-1BB ligand. The direct oncolytic effect coupled with immune stimulation by RP3 in the TME is intended to provide systemic antitumor activity and synergize with anti–PD-1/PD-L1 agents, such as Atezo. Preclinical data have demonstrated improved distribution of oncolytic HSV within tumors in combination with Bev, supporting the clinical combination of RP3 with Bev. This study will evaluate the safety and efficacy of RP3 combined with Atezo plus Bev as first- (1L) and second-line (2L) systemic therapies for unresectable and advanced HCC (NCT05733598). Methods: The 1L and 2L cohorts will each enroll up to 30 pts. Pts in the 1L cohort may not have received prior systemic treatment; pts in the 2L cohort must have progressed on or following 1 prior line of systemic therapy, which must have included a PD-1/PD-L1–directed agent. Key inclusion criteria include advanced unresectable HCC with ≥1 measurable tumor of ≥1 cm in longest diameter, Child-Pugh class A, and an Eastern Cooperative Oncology Group performance status of 0 to 1. Key exclusion criteria include untreated esophageal and/or gastric varices with bleeding or at high risk for bleeding and macroscopic invasion of the tumor into any major blood vessel(s) and/or main bile ducts. Pts with a history of medically refractory hepatic encephalopathy and/or hepato-renal syndrome are also excluded. Pts in the 1L cohort will receive Atezo 1200 mg and Bev 15 mg/kg every 3 weeks (Q3W) together with RP3 intratumorally Q3W for a total of up to 8 doses. Pts in the 2L cohort will receive RP3 every 2 weeks for 4 doses with Bev Q3W starting on cycle (C)1 day (D)1, then RP3 and Bev Q3W for up to 4 more doses with Atezo Q3W being added on C4D1. The primary endpoint is the overall response rate (ORR) by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Secondary endpoints are safety, ORR using HCC modified RECIST, duration of response, complete response rate, and progression-free survival. Clinical trial information: NCT05733598 .

A phase 1b/2 study to evaluate the safety and efficacy of TTI-101 as monotherapy and in combination in advanced hepatocellular carcinoma.

TPS577 Background: STAT3 (signal transducer and activator of transcription 3) is a key regulatory protein positioned at the intersection of many signaling pathways integral to the survival and immune evasion of cancer cells. Persistent STAT3 activation has been linked to pathological conditions, including chronic inflammation and fibrosis, both of which play essential roles in the pathogenesis of hepatocellular carcinoma (HCC), and is observed in up to 95% of HCC cases. TTI-101 is a first-in-class, orally delivered, small molecule, direct inhibitor of STAT3 activation. TTI-101 monotherapy demonstrated tumor growth arrest as well as reversal of liver injury and fibrosis in a genetically modified mouse model (Hep Pten- ) which recapitulates the pathogenesis of HCC in non-alcoholic fatty liver disease (NAFLD), as well as in combination with immune checkpoint inhibition in a humanized HCC mouse model.1,2 TTI-101 monotherapy was found to be well tolerated in a Phase 1 trial conducted in patients (pts) with advanced solid tumors (NCT03195699). Of 15 evaluable HCC pts, 60% demonstrated clinical benefit, including 20% confirmed partial responses (median duration=10.5 months). All pts were relapsed/refractory to standard of care (SOC; median prior systemic therapy=2), including anti-PD-(L)1 based therapy. Methods: NCT05440708 is a multicenter, open-label, study with primary endpoints including safety and efficacy of TTI-101 as monotherapy and in combination with SOC agents. Patients are enrolled to one of three treatment cohorts based upon prior therapy. Cohort A: TTI-101 (monotherapy), pts who have received up to 3 prior lines of systemic therapy. Cohort B: TTI-101 + pembrolizumab, pts who have progressed following ≥ 2 cycles of first-line anti-PD-(L)1 based therapy. Cohort C: TTI-101 + atezolizumab/bevacizumab, patients who are systemic treatment-naïve. The study consists of 2 parts for each cohort (Phase 1b and Phase 2). During Phase 1b, up to 3 dose levels of TTI-101 will be tested for each cohort to determine the RP2D, using a 3+3 design. Subsequent to RP2D determination, enrollment to Phase 2 will commence (Cohort A n=30, Cohort B n=30, Cohort C n=40). Treatment will continue until disease progression, unacceptable toxicity, withdrawal of consent, discontinuation based on investigator discretion, or study termination. Secondary and exploratory endpoints include pharmacodynamic effects of TTI-101 and evaluation of candidate biomarkers for anti-tumor activity. Enrollment is simultaneously ongoing in Cohorts A, B, and C of the Phase 1b study. 1. Jung KH, et al. Clin Cancer Res. 2017;23(18):5537-5546. 2. Zhao Y, et al. Hepatology. 2021. Clinical trial information: NCT05440708 .