Long-term Responders Research Articles

Deep Brain Stimulation of the Central Lateral and Ventral Posterior Thalamus for Central Poststroke Pain Syndrome: Preliminary Experience

ObjectiveThe beneficial effects of thalamic deep brain stimulation (DBS) at various target sites in treating chronic central neuropathic pain (CPSP) remain unclear. This study aimed to evaluate the effectiveness of DBS at a previously untested target site in the central lateral (CL) thalamus, together with classical sensory thalamic stimulation (ventral posterior [VP] complex). Materials and MethodsWe performed a monocentric retrospective study of a consecutive series of six patients with CPSP who underwent combined DBS lead implantation of the CL and VP. Patient-reported outcome measures were recorded before and after surgery using the numeric rating scale (NRS), short-form McGill pain questionnaire (sf-MPQ), EuroQol 5-D quality-of-life questionnaire, and Beck Depression Inventory. DBS leads were reconstructed and projected onto a three-dimensional stereotactic atlas. ResultsNRS—but not sf-MPQ–rated pain intensity—was significantly reduced throughout the follow-up period of 12 months compared with baseline (p = 0.005, and p = 0.06 respectively, Friedman test). At the last available follow-up (12 to 30 months), three patients described a more than 50% reduction. Two of the three long-term responders were stimulated in the CL (1000 Hz, 90 μs, 3.5–5.0 mA), whereas the third preferred VP complex stimulation (50 Hz, 200 μs, 0.7–1.2 mA). No persistent procedure- or stimulation-associated side effects were noted. ConclusionsThese preliminary findings suggest that DBS of the CL might constitute a promising alternative target in cases in which classical VP complex stimulation does not yield satisfactory postoperative pain reduction. The results need to be confirmed in larger, prospective series of patients.

Long-Term Response to Tyrosine Kinase Inhibitors for Metastatic Renal Cell Carcinoma.

Background: Tyrosine kinase inhibitors (TKIs) prolong progression-free survival (PFS) in patients with metastatic renal cell carcinoma (mRCC), some of which may achieve long-term responses. Herein, we report clinical and pathological characteristics of patients who achieved long-term responses during first-line TKI treatment. Methods: Patients receiving TKI as first-line therapy from January 2010 to December 2017 in seven Italian Oncology Centers were reviewed. Sixty-six patients were considered as long-term responders, as they remained progression-free for 36 months or more during TKI treatment. A logistic regression model was performed to evaluate the effect of each clinical-pathological variable on the probability of responding long-term. Results: A total of 335 patients with a median age of 66 years were included in the analysis. The median PFS and overall survival among the long-term responders was 70 and 106 months, respectively. At a landmark PFS analysis performed 36 months after the start of treatment, the median PFS was 34 months. Multivariate analysis from all patients identified previous nephrectomy, Eastern Cooperative Oncology Group Performance Status (ECOG PS) < 1, and lack of liver metastasis as favorable prognostic factors for long-term response. Female gender and lack of liver metastasis positively correlated with long-term responses in favorable-risk-score population, as well as ECOG PS < 1 in intermediate-poor risk score population. Patients Summary: Previous surgery, clinical condition, and lack of liver metastasis may predict long-term responses to tyrosine kinase inhibitors. Conclusions: TKIs can lead to a long-term response in a subset of patients with metastatic RCC. Previous nephrectomy, optimal performance status (ECOG PS = 0), and lack of liver metastasis may predict long-term responses.

Targeting Homologous Recombination Deficiency in Ovarian Cancer with PARP Inhibitors: Synthetic Lethal Strategies That Impact Overall Survival.

Simple SummarySynthetic lethality approaches to cancer therapy involves combining events to cause cancer cell death. Using this strategy, major advances have occurred in the treatment of women with ovarian cancer who have defects in the Homologous Recombination Repair (HRR) pathway. When the HRR pathway is defective, due to mutations or epigenetic changes in genes such as BRCA1 or BRCA2, cells can no longer accurately repair double strand breaks (DSBs). Capitalising on this weakness, pharmacological inhibition of poly (ADP-ribose) polymerase (PARP) that function to repair single strand breaks (SSBs) leads to synthetic lethality in cells with defective HRR. PARP inhibitors (PARPis) including olaparib, niraparib and rucaparib are approved for the clinical management of women with ovarian cancer. Understanding and overcoming issues of acquired resistance to PARPis, extending these strategies to benefit more patients and combining PARPis with other drugs, including immunotherapies, are of high priority in the field today.The advent of molecular targeted therapies has made a significant impact on survival of women with ovarian cancer who have defects in homologous recombination repair (HRR). High-grade serous ovarian cancer (HGSOC) is the most common histological subtype of ovarian cancer, with over 50% displaying defective HRR. Poly ADP ribose polymerases (PARPs) are a family of enzymes that catalyse the transfer of ADP-ribose to target proteins, functioning in fundamental cellular processes including transcription, chromatin remodelling and DNA repair. In cells with deficient HRR, PARP inhibitors (PARPis) cause synthetic lethality leading to cell death. Despite the major advances that PARPis have heralded for women with ovarian cancer, questions and challenges remain, including: can the benefits of PARPis be brought to a wider range of women with ovarian cancer; can other drugs in clinical use function in a similar way or with greater efficacy than currently clinically approved PARPis; what can we learn from long-term responders to PARPis; can PARPis sensitise ovarian cancer cells to immunotherapy; and can synthetic lethal strategies be employed more broadly to develop new therapies for women with ovarian cancer. We examine these, and other, questions with focus on improving outcomes for women with ovarian cancer.

424P Avelumab added to FOLFIRI plus cetuximab followed by avelumab maintenance in patients with previously untreated RAS wild-type colorectal cancer: The phase-II FIRE-6 (AIO KRK-0118)

The FIRE-6 avelumab study (AIO KRK-0118) was performed in RAS-wild-type mCRC patients. This multi-center single-arm study tested the efficacy of avelumab maintenance during 1st-line therapy after 4 cycles of induction treatment with FOLFIRI plus cetuximab (FOLFIRI/Cet) followed by 4 cycles of combination treatment using FOLFIRI/Cet plus avelumab. Subsequently, treatment was continued with avelumab until progression or intolerable toxicity. Patients received FOLFIRI (irinotecan plus 5-FU/FA) every two weeks plus cetuximab weekly at the standard dosing schedule. After 4 cycles of therapy, avelumab (10mg/kg q2w) was added to FOLFIRI/Cet and continued for another 4 cycles before maintenance with avelumab monotherapy was started. Median progression-free survival (PFS) according to RECIST v1.1 was evaluated as primary endpoint. With a target PFS ≥ 12.88 months, the study was designed to reject the null hypothesis of PFS ≤8.0 months with a power of 80% at a one-tailed significance level of 0.025. Secondary endpoints included ORR, OS, safety, and tolerability. From November 2019 to June 2021, 57 patients were treated within the study protocol. Treatment with FOLFIRI/Cet plus avelumab was well tolerated and no new or unexpected toxicities were observed. Median PFS was 7.0 months in 47 evaluable patients. Overall response rate was 73.2% with a disease control rate of 87.5%. Median time on avelumab maintenance was 1.9 months with a range up to 15.6 months. Median OS was not reached at the time of the latest data cut-off with only 21.4% of OS events had occurred. With a median PFS of 7.0 months, FIRE-6 avelumab did not reach its pre-specified endpoint. Avelumab maintenance after FOLFIRI/Cet therefore is not effective to postpone disease progression after FOLFIRI/Cet induction therapy in first-line RASwt mCRC patients. Some long-term responders are present and will be further analyzed. FOLFIRI/Cet plus avelumab is safe and feasible as no unexpected toxicities occurred. FIRE-6 avelumab confirms the efficacy with respect to tumor response and disease control of FOLFIRI plus cetuximab as first-line treatment of patients with RAS wild-type mCRC.

CN65 Feasibility, acceptability and utility of a pilot nurse-led survivorship program for people with metastatic melanoma

Immune checkpoint inhibitors (ICI) and targeted therapy (TT) have improved the survival of people with metastatic melanoma (PwMM), with 50% achieving durable disease control. However, there are no models of survivorship care which address their physical and psychosocial concerns. MELCARE is a nurse-led survivorship program for PwMM who are long-term responders to ICI/ TT. It consists of two telehealth consultations three months apart, needs assessment using the NCCN Distress Thermometer (DT) and Problem List (PL), and creation of a survivorship care plan (SCP).

Long-Term Responders After Autologous Stem Cell Transplantation in Multiple Myeloma

IntroductionMultiple myeloma (MM) is considered an incurable hematological neoplasm. For transplant-eligible patients, initial treatment includes an induction phase followed by an autologous stem cell transplantation (ASCT). Despite the introduction of several drugs in the past years, relapses still occur. Nevertheless, some patients achieve sustained responses after successful induction treatment and ASCT.MethodsWe retrospectively evaluated all patients diagnosed with MM in our institution who underwent induction treatment and ASCT between 1990 and 2015. The subset of patients who achieved a sustained response (any degree) for 5 or more years after ASCT without further treatment or signs of progression were distinguished as “long-term responders” (LTRs). In the non-LTR group, a cohort referred to as “prolonged responders” (PLRs) showed sustained response of at least 5 years after ASCT but eventually relapsed. We collected and analyzed clinical and laboratory data.ResultsTwo hundred and fifty patients were diagnosed with MM and received induction treatment and ASCT at our institution in the study period. Among them, 54 (21.6%) patients met the criteria for LTR. Some diagnostic features such as a younger age, female gender, ECOG performance status of 0, lower International Staging System (ISS) stage, lower bone marrow plasma cell infiltration, and lower serum levels of calcium, C-reactive protein, and lactate dehydrogenase (LDH) were found to be more prevalent in LTR. Female gender, an ECOG performance status of 0, a localized Durie-Salmon stage, an ISS of I–II, the absence of bone disease, and an LDH within normal range were also predictive of longer progression-free survival (PFS) and overall survival (OS) in the whole cohort. The depth of the response achieved after induction and ASCT as well as the administration of an IMID-based maintenance regimen may play a role in the differences observed on PFS between cohorts. A detectable M-protein with a monoclonal gammopathy of undetermined significance (MGUS)-like behavior was detected in one-third of LTR after ASCT. Although relapses continue to occur in patients who achieve a 5-year treatment-free period after ASCT, a plateau is observed in the survival curves at approximately 21 years of follow-up.

Abstract 3577: First-in-human phase I study of intraperitoneally administered interferon-activated autologous monocytes in platinum-resistant ovarian cancer

Abstract Background: Ovarian cancer is the most lethal gynecologic cancer and is intrinsically resistant to immunotherapies. Previous work has demonstrated superior response rates with intraperitoneally (IP) directed therapies, providing the rationale for IP immunotherapy. Methods: A previously published model system in which OVCAR ovarian cancer spheroids are killed by IFN-activated human monocytes was further characterized using confocal microscopy, global gene expression analysis, flow cytometry, and knockout/knockdown of key genes in the TRAIL-DR4/DR5 pathway. These results were translated into a phase I dose escalation trial in which 3-6 patients with platinum-resistant or refractory ovarian cancer were enrolled into 4 cohorts and treated IP q28 days with Peginterferon alfa-2b (25-250 mcg) and Interferon gamma-1b (5-50 mcg), with or without autologous monocytes (75-750 x 106 cells), in order to determine the recommended phase II dose (RP2D). Results: Confocal microscopy of IFN-activated monocytes demonstrated migration into OVCAR spheroids and destruction of the spheroids and global gene expression analysis identified TRAIL as a ligand on monocytes upregulated by IFN treatment. Disruption of TRAIL receptors DR4/DR5 or deletion of CASPASE8 on OVCAR cells largely abrogated killing. IFN-activated human monocytes were able to kill IP-injected OVCAR tumor cells in a mouse xenograft model, and IFN-activated monocytes from ovarian cancer patients were able to kill OVCAR spheroids as effectively as those from healthy donors. 18 patients were subsequently enrolled on a phase I trial (median age, 61 years; median 5 prior therapies). 1 of 3 patients at the second dose level experienced a dose-limiting toxicity (grade 3 anemia) and no subsequent DLTs were observed. The RP2D was defined as 250mcg IFNa/50mcg IFNg/750 x 106 cells. The only treatment-related grade 3 or higher adverse events occurring in more than one patient were lymphocyte decrease (33.3%) and abdominal pain (11.1%). The best response observed was partial response (PR) in 2/9 RECIST-evaluable patients, and 1 additional patient had a CA-125 response with &amp;gt;50% reduction. 4/9 patients had stable disease. Four patients were able to receive 5+ cycles (range 1-10 cycles). Biomarker analyses demonstrated that these long-term responders had a lower level of T-regulatory cells at baseline, but exhibited marked increase in myeloid derived suppressor cells (MDSC) at the time of tumor progression. Conclusion: These findings characterize the mechanism of a novel cellular immunotherapy for ovarian cancer which is well tolerated with evidence of clinical activity in a heavily pretreated patient population. This therapy may serve as the backbone for a combination immunotherapy regimen incorporating additional agents targeting T-regulatory cells and/or MDSCs. Citation Format: Christopher B. Cole, Daniel S. Green, Franklin Ning, Kathryn Zoon, Lindsey B. Rosen, Steven M. Holland, Christina M. Annunziata. First-in-human phase I study of intraperitoneally administered interferon-activated autologous monocytes in platinum-resistant ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3577.

Blood gene expression changes in metastatic lung cancer under first-line immunotherapy according to clinical response.

e21141 Background: First-line pembrolizumab monotherapy is a standard treatment for metastatic non-small-cell lung cancer (NSCLC) with high PD-L1 expression (TPS ≥50%). However, many patients do not respond, and reliable biomarkers are lacking. Methods: Blood samples of 33 patients with metastatic NSCLC were analyzed at baseline (BL) and after four cycles of pembrolizumab monotherapy (FU). The expression of 12 genes involved in tumor-specific immune responses ( FAS, RORgt, FOXP3, IFNγ, FASLv1, PRF1, GATA3, PD1, CD247, GZMB, MKI67, TBX21) in whole blood RNA was quantified by RT-PCR in absolute terms using plasmids as standards. Results: Gene expression was significantly higher after immunotherapy for 11/12 genes analyzed ( FAS, RORgt, FOXP3, IFNγ, FASLv1, PRF1, GATA3, PD1, CD247, GZMB, TBX21 with fold changes [FC] 1.99 – 5.45; all p &lt; 0.001). Blood neutrophil and total leukocyte counts were significantly decreased (ANC BL:7.65/nl vs. FU:5.36/nl, p = 0.024; Leu BL:10.65/nl vs. FU:7.78/nl, p = 0.032), while lymphocyte counts did not change (ALC BL:1.41/nl vs. FU:1.47/nl, p = 0.267). Increases in the expression of RORgt, FASLv1, PRF1, PD1, CD247, GZMB and TBX21 remained significant (FC 1.9 – 3.7; all p &lt; 0.001) even after correction for the blood lymphocyte/leukocyte ratio (Ly/Lc BL:0.151 vs. FU:0.197, p = 0.003). Patients with long-term response (LTR, i.e. lasting &gt; 6 months) had significantly higher increases in the expression of 8 genes ( RORgt, FOXP3, IFNγ, FASLv1, GATA3, PD1, CD247, TBX21) compared with patients with rapid disease progression within 3 months (RP) (FC 2.34 – 4.62, all p &lt; 0.05). There were no significant differences (FU-BL) between LTR and RP regarding ANC (RP:-1.00/nl vs. LTR:-2.63/nl, p = 0.50), ALC (RP:-0,14/nl vs. LTR:+0,12/nl, p = 0,33) or Ly/Lc (RP:0.015 vs. LR:0.0542, p = 0.259). Conclusions: Pembrolizumab monotherapy of metastatic NSCLC causes significant increases in the blood expression for several genes including FAS, RORgt, FOXP3, IFNγ, FASLv1, PRF1, GATA3, PD1, CD247, GZMB, TBX21, as well as a decrease in circulating neutrophiles and total leucocytes. Long-term responders have more pronounced blood gene expression changes, which appear to correlate with long-term benefit, in contrast to blood count changes, which are not indicative. These results are currently being validated in a larger prospective study.

Clinical insights from the rucaparib access program in Spain: A sub-analysis of long-term responders by GEICO.

e17562 Background: Rucaparib is a PARP inhibitor approved for the treatment of high-grade ovarian cancer (HGOC). Clinical trials have demonstrated its benefit both as maintenance therapy (MTN) for platinum (Pt)-sensitive recurrent HGOC, and as treatment (Tx) in BRCA-mutated relapsed or recurrent HGOC patients. Here we analyze real-world data from the rucaparib early access program (RAP) in Spain with focus in the long-term responder patients (LTR). Methods: A retrospective observational study was performed by GEICO at 22 hospitals in Spain that had treated patients within the RAP. Adult women with HGOC, fallopian tube, or primary peritoneal cancer were included and received rucaparib (600 mg BID) in the MTN, Tx Pt-sensitive or Tx Pt-resistant setting. Patients’ characteristics, medical history, safety, efficacy, and dosing data were collected. In this analysis, long-term response was defined as progression-free survival (PFS) ≥12 months for the MTN group and ≥6 months for the Tx group. LTR were stratified based on the rucaparib indication (MTN/Tx). Results: Between July 2020 and February 2021, 51 patients were recruited: 18 received rucaparib as MTN and 33 as Tx. In the MTN group, 6 patients (33.3%) were LTR, with a median age of 65 years (54-79). Of them, 2 patients (33.2%) harbored BRCA or RAD51C mutations. The median number of prior lines was 3 (2-6), being ≥5 in 33.2%, and 50.0% received prior bevacizumab. ECOG PS was ≤1 in all these patients, 66.6% had measurable disease and 50.0% achieved a partial response to prior Pt-based chemotherapy. In the Tx group, 10 patients (30.3%) were LTR, with a median age of 71 years (47-86). All of them harbored BRCA and/or RAD51C mutations. The median number of prior lines was 6 (2-9), with 60.0% receiving ≥5 prior lines, and 50.0% received prior bevacizumab. Regarding Pt-status, 40.0% of patients were Pt-sensitive and 60.0% were Pt-resistant. The ECOG PS was ≥1 in 30.0% of patients and 60.0% had measurable disease. The median PFS of LTR was not achieved in the MTN group and was 10.9 months (95% CI: 7.0-16.7) in the Tx group. Adverse events (AE) of any grade were reported in 66.6% of LTR within the MTN group and in 100.0% within the Tx group, while AE of grade ≥3 occurred in 16.6% and 50.0%, respectively. Rucaparib dose was reduced in 50.0% of LTR in the MTN group and 80.0% in the Tx group. Discontinuation rate due to rucaparib toxicity was 20.0% in the Tx group and there were no discontinuations due to toxicity in the MTN group. No new safety signals were detected. At present, 3 and 1 patients are still receiving rucaparib as MTN and Tx, respectively. Conclusions: A durable response was achieved in a notable proportion of patients, even despite their unfavorable conditions at treatment initiation (heavily pre-treated patients, partial response or resistance to Pt, or high volume of disease). The safety profile of rucaparib in this real-world setting is consistent with that reported in clinical trials.

PSMA PET findings in patients with undetectable PSA more than 3 years after docetaxel for metastatic castration-sensitive prostate cancer (mCSPC).

e17046 Background: Multiple treatment options combined with androgen deprivation therapy (ADT) provide a survival advantage in mCSPC. In this prospective study, mCSPC patients were treated with docetaxel and Prostvac, a therapeutic cancer vaccine. Since initiation of the study, a phase 3 trial of Prostvac did not show independent clinical activity in metastatic castration-resistant prostate cancer. Still, this study offers a chance to evaluate responses to docetaxel-based therapy in mCSPC. More specifically, with FDA approval of prostate-specific membrane antigen (PSMA) PET imaging in just the last year, there is a paucity of data regarding the use of this scan in long-term responders to therapies for mCSPC. Methods: Eligible patients included those with mCSPC and ECOG PS of ≤ 2. As per the CHAARTED regimen, patients started docetaxel within 4 months of initiating ADT with a plan to receive 75mg/m2 for 6 cycles. Patients were randomized to receive Prostvac prior to, concurrent with, or after docetaxel. Restaging was done annually with CT and Tc99 bone scan. The study was powered to evaluate immune responses, which is being reported separately. For this analysis, patients were evaluated as one group. Ten patients are in follow up with continued PSA values of ≤ 0.2 ng/mL and 7/10 were evaluated with 18F-DCFPyL PSMA PET. Results: Seventy-three patients enrolled. Median age was 63 years with a range of 41-86 years. Race distribution was 71.6% White, 20.3% Black, 4.1% other, and 4.1% unknown. Gleason 6, 7, and 8 to 10 was 4.1%, 21.6%, and 68.9% of patients, respectively, with 5.4% being unknown. Median pre-ADT PSA was 34.75 ng/mL. Low-volume disease represented 41.1% of patients and high-volume was 58.9%. After 2 years from the start of ADT, 22% of patients had PSA values of ≤ 0.2 ng/mL. This included 37% of the low-volume group and 12% of the high-volume group. Three years from starting ADT, 14% of patients had PSA values ≤ 0.2 ng/mL (20% of the low-volume group, 9% of the high-volume group). Of the 7 patients who remain in follow-up with PSA values ≤ 0.2 ng/mL and who were evaluated with PSMA PET, median time from start of ADT was 4 years with a range of 3.5-6 years. These patients either had no evidence of disease or minimal residual findings on CT/Tc99 bone scan. Four of the 7 patients still had residual areas of uptake on PSMA PET. Conclusions: Patients treated with docetaxel for mCSPC have the potential for long-term clinical responses. In these long-term responders, despite prolonged PSA response and minimal findings on conventional CT and Tc99 scans, more than half of patients still had findings on PSMA PET imaging. Further studies are required to better understand the clinical implications of these findings and the role of PSMA PET in mCSPC. Clinical trial information: NCT02649855.

A Retrospective Comparison of Long-Term Treatment Results of Subcutaneous Stimulation and Spinal Cord Stimulation for Chronic Neuralgia

ObjectivesSpinal cord stimulation (SCS) is known to be an effective long-term treatment option for chronic neuropathic pain. Subcutaneous stimulation (SubQ) is increasingly used to treat chronic back and neck pain, but long-term outcomes are unclear. Materials and MethodsPatients with neurostimulation devices implanted during the past 16 years were evaluated. Their continuation or termination of the treatment was taken as a measure of long-term treatment success. Age, sex, underlying pain condition, stimulation modality (SCS, SubQ, or hybrid), occurrence, and reasons for treatment termination were documented. Patients were classified as long-term responders and long-term nonresponders and analyzed with their clinical data and stimulation modality. The sample consisted of 98 patients. Of these, 66 were treated with SCS, 21 with SubQ, and 11 with a hybrid system. ResultsApproximately 61.3% of patients receiving SubQ terminated the treatment within two years because of ineffectiveness, whereas only 28.8% of patients receiving SCS terminated their stimulation. Back and neck pain were associated with treatment termination (p = 0.011). SubQ was also significantly associated with treatment termination. ConclusionsSubQ seems not to provide substantial long-term pain relief for back and neck pain because most patients abandoned their stimulation therapy.

Fecal microbiota transplantation to improve efficacy of immune checkpoint inhibitors in renal cell carcinoma (TACITO trial).

TPS407 Background: Renal cell carcinoma (RCC) is the 6° most common cancer in men and the 8° in women in the USA. In Italy RCC incidence was 11,500 new cases in 2017, while mortality was 3,371 cases in 2015. Increasing evidence suggests that response to immune checkpoint inhibitors (ICIs), a novel treatment for advanced RCC (aRCC) and other epithelial tumors, can be influenced by the patient gut microbiota. Fecal microbiota transplantation (FMT) is a novel treatment option aimed to restore healthy gut microbiota, and is the most effective therapy for recurrent C. difficile infection. Preliminary nonrandomized findings show that FMT is able to improve efficacy of ICIs in patients with advanced melanoma. The aim of this study is to evaluate, through a double-blinded placebo-controlled randomized clinical trial, the efficacy of targeted FMT (from donors who are responding to ICIs) in improving response rates to ICIs in subjects with aRCC. Methods: 50 patients who are about to receive, or have started by &lt;8 weeks, pembrolizumab + axitinib as first-line therapy for aRCC will be enrolled. Exclusion criteria include major comorbidities, concomitant GI or autoimmune disorders, or HIV, HBV, HCV infection, continuative corticosteroid therapy, previous treatment with systemic immune-suppressants or immune-modulatory drugs, antibiotic therapy within 4 weeks prior to enrollment. Stool samples and clinical data will be collected at baseline. Then, patients will be randomized to donor FMT or placebo FMT. They will receive the first infusion by colonoscopy and then oral frozen fecal or placebo capsules (8 capsules t.i.d.) 90 and 180 days after the first FMT. Stool donors will be searched among long-term (&gt;12 months) responders to ICIs, and will be selected by following protocols recommended by international guidelines. Patients in the FMT group will always receive feces from the same donor throughout the three fecal transplants. Frozen fecal batches and frozen fecal capsules will be manufactured according to international guidelines. Patients will be followed-up 7, 15, 30, 90, 180, 270, and 360 days after randomization for clinical evaluation and collection of stool samples. Patients will also undergo radiological assessment at 90, 180, 270 and 360 days after randomization. Microbiome analysis will be performed with shotgun metagenomics. The primary endpoint is the progression-free survival (PFS) at 12 months. Secondary endpoints are: objective response rate at 12 months; overall survival at 12 months; adverse events after FMT; microbiome changes after FMT. Sample size calculation was based on the hypothesis that FMT can improve the 1-year PFS rate from 60% (reported 1-year PFS for SOC) to 80% wen associated to SOC. Clinical trial information: NCT04758507.

Phase 2 Trial (POLA Study) of Lurbinectedin plus Olaparib in Patients with Advanced Solid Tumors: Results of Efficacy, Tolerability, and the Translational Study.

Simple SummaryGenomic instability (GI) is a transversal phenomenon in oncology, constituting a hallmark of cancer. In gynecological malignancies, the predictive value of GI has been described and is mainly caused by alterations in the homologous recombination repair (HRR) genes, such as BRCA1/2. The POLA clinical trial constitutes an ideal substrate used to study the correlation between GI and response to combined therapy of lurbinectedin plus olaparib in solid tumors. In this context, we developed an approach based on next-generation sequencing, capable of shedding information about Copy Number Variations (CNV) as a surrogate of GI and genotyping of homologous recombination repair genes. Additionally, some algorithms used to extract GI parameters were tested and benchmarked, selecting the most informative mutational and GI features as potential predictive biomarkers for the drug combination explored in the POLA trial.We hypothesized that the combination of olaparib and lurbinectedin maximizes DNA damage, thus increasing its efficacy. The POLA phase 1 trial established the recommended phase 2 dose of lurbinectedin as being 1.5 mg (day 1) and that of olaparib as being 250 mg/12 h (days 1–5) for a 21-day cycle. In phase 2, we explore the efficacy of the combination in terms of clinical response and its correlation with mutations in the HRR genes and the genomic instability (GI) parameters. Results: A total of 73 patients with high-grade ovarian (n = 46), endometrial (n = 26), and triple-negative breast cancer (n = 1) were treated with lurbinectedin and olaparib. Most patients (62%) received ≥3 lines of prior therapy. The overall response rate (ORR) and disease control rate (DCR) were 9.6% and 72.6%, respectively. The median progression-free survival (PFS) was 4.54 months (95% CI 3.0–5.2). Twelve (16.4%) patients were considered long-term responders (LTR), with a median PFS of 13.3 months. No clinical benefit was observed for cases with HRR gene mutation. In ovarian LTRs, although a direct association with GI and a total loss of heterozygosity (LOH) events was observed, the association did not reach statistical significance (p = 0.055). Globally, the total number of LOHs might be associated with the ORR (p =0.074). The most common grade 3–4 toxicities were anemia and thrombocytopenia, in 6 (8.2%) and 3 (4.1%) patients, respectively. Conclusion: The POLA study provides evidence that the administration of lurbinectedin and olaparib is feasible and tolerable, with a DCR of 72.6%. Different GI parameters showed associations with better responses.

Five-year Follow-up of Patients With Head and Neck Cancer Treated With Nivolumab and Long-term Responders for Over Two Years.

A long-term effect has been confirmed in clinical practice since the introduction of nivolumab for treating various malignant tumors. A similar phenomenon is speculated to occur in head and neck cancer; however, details remain unclear due to the lack of long-term reports. We aimed to investigate the five-year outcomes in long-term responders for over two years, and evaluate the optimal duration of therapy with nivolumab. In this retrospective observational study, we analyzed 203 cases of recurrent/metastatic head and neck squamous cell carcinoma (R/MHNSCC), including 33 long-term responders. The median overall survival (OS), 5-year OS, median progression-free survival (PFS), and 5-year PFS values in the 203 cases were 13.1 months, 19.2%, 3.1 months, and 13.2%, respectively. Of the 33 long-term responders, 14 (42.4%) continued using nivolumab for more than 2 years. The remaining 19 patients (57.6%) discontinued nivolumab. The most common reason for discontinuation was severe immune-related adverse events (irAEs) (9 cases; 27.3%); in these 9 cases, the median disease-free survival was 33.2 (range=10.7-44.3) months. Nine patients (21.2%) were considered to have progressive disease (PD) after at least 2 years of administration, and 3 patients (9.1%) requested to discontinue treatment because a complete response (CR) was achieved. This study demonstrated the durable and long-term benefit of nivolumab in R/MHNSCC. In the future, we aim to accumulate real-world data for the establishment of criteria for completion of nivolumab treatment in long-term responders.

Assessment of Treatment Effects and Long-term Benefits in Immune Checkpoint Inhibitor Trials Using the Flexible Parametric Cure Model

Compared with standard cytotoxic therapies, randomized immune checkpoint inhibitor (ICI) phase 3 trials reveal delayed benefits in terms of patient survival and/or long-term response. Such outcomes generally violate the assumption of proportional hazards, and the classical Cox proportional hazards regression model is therefore unsuitable for these types of analyses. To evaluate the ability of the flexible parametric cure model (FPCM) to estimate treatment effects and long-term responder fractions (LRFs) independently of prespecified time points. This systematic review used reconstructed individual patient data from ICI advanced or metastatic melanoma and lung cancer phase 3 trials extracted from the literature. Trials published between January 1, 2010, and October 1, 2019, with long-term follow-up periods (maximum follow-up, ≥36 months in first line and ≥30 months otherwise) were selected to identify LRFs. Individual patient data for progression-free survival were reconstructed from the published randomized ICI phase 3 trial results. The FPCM was applied to estimate treatment effects on the overall population and on the following components of the population: LRF and progression-free survival in non-long-term responders. Results obtained were compared with treatment effects estimated using the Cox proportional hazards regression model. In this systematic review, among the 23 comparisons studied using the FPCM, a statistically significant association between the time-to-event component and experimental treatment was observed in the main analyses and confirmed in the sensitivity analyses of 18 comparisons. Results were discordant for 4 comparisons that were not significant by the Cox proportional hazards regression model. The LRFs varied from 1.5% to 12.7% for the control arms and from 4.6% to 38.8% for the experimental arms. Differences in LRFs varied from 2% to 29% and were significantly increased in the experimental compared with the control arms, except for 4 comparisons. This systematic review of reconstructed individual patient data found that the FPCM was a complementary approach that provided a comprehensive and pertinent evaluation of benefit and risk by assessing whether ICI treatment was associated with an increased probability of patients being long-term responders or with an improved progression-free survival in patients who were not long-term responders.

No evidence of disease versus residual disease in long-term responders to first-line HER2-targeted therapy for metastatic breast cancer.

Long-term response to HER2-targeted therapies is infrequent in metastatic breast cancer (MBC). We evaluated clinical characteristics of HER2-positive MBC patients with no evidence of disease (NED) vs residual disease (RES) experiencing long-term response to first-line HER2-targeted therapy. Patients receiving first-line chemotherapy-trastuzumab (CT) or taxane-trastuzumab-pertuzumab (THP) with response duration ≥2-fold higher than in phase II/III trials (CT [18.2 months]; THP [40.4 months]) were included. Clinical characteristics and radiographic review for NED or RES was evaluated by Cox-regression (hazard ratio; HR) or Kaplan-Meier (log-rank). Characteristics associated with NED were evaluated by logistic regression (Odds; OR). From 01/2005-01/2016, N = 103 (4.6%) patients were identified. In multivariate analyses, NED (N = 46) showed improved progression-free (PFS) and overall survival (OS) [p < 0.001] versus RES (N = 57), with high 5-year PFS/OS for NED (93.2%/97.4%) relative to RES (10.6%/61.3%). Premenopausal status (p = 0.006), de-novo metastases (p = 0.002), and no palliative radiotherapy (p = 0.01) were associated with NED. Overall,6/7 (85.7%) patients with NED were alive and disease-free after discontinuing HER2 treatment (≥1 year) versus 1/17 (5.9%) with RES. Long-term responders with NED have better survival compared to RES. Premenopausal status and de novo metastatic disease are associated with NED. Prospective studies of HER2 therapy discontinuation with NED in MBC are warranted.

In Vitro Generated Dendritic Cells of Leukemic Origin Predict Response to Allogeneic Stem Cell Transplantation in Patients With AML and MDS.

Allogeneic stem cell transplantation (alloSCT) is the treatment of choice for many patients with acute myeloid leukemia (AML) and myelodysplastic syndrome. The presentation of leukemic or allospecific antigens by malignant blasts is regarded as a crucial trigger for an effective allogeneic immune response. Conversely, insufficient stimulatory capacity by the leukemic blasts is thought to be a relevant escape mechanism from cellular immunotherapy (alloSCT). Our purpose was to test, whether the ability of malignant blasts to differentiate in vitro toward dendritic cells of leukemic origin (DCleu) is associated with clinical outcome. We isolated leukemic blasts from peripheral blood or bone marrow of AML and myelodysplastic syndrome patients before alloSCT (n=47) or at relapse after alloSCT (n=22). A panel of 6 different assays was used to generate DCleu in vitro. Results were correlated with clinical outcome. DCleu could be generated from all 69 samples. Significantly higher mean frequencies of DCleu were found in clinical long-term responders versus nonresponders to SCT (76.8% vs. 58.8%, P=0.006). Vice versa, the chance for response to SCT was significantly higher, if a DCleu+/dendritic cells (DC) ratio of >50% could be reached in vitro (P=0.004). Those patients were characterized by a longer time to relapse (P=0.04) and by a higher probability for leukemia-free survival (P=0.005). In vitro generation of DC and DCleu from leukemic blasts correlated with the clinical outcome. This observation may support a role of leukemic antigen presentation by "leukemia-derived DC" for the stimulation of an allogeneic immune response in AML.

Patient-reported outcome measures after 8weeks of mepolizumab treatment and long-term outcomes in patients with severe asthma: an observational study.

Background The novel anti-IL-5 drug mepolizumab improves asthma outcomes in the majority but not all patients with severe eosinophilic asthma. Currently it is difficult to predict an individuals' chance of being a responder. Early changes in patient-reported outcome measures may contribute to the prediction of long-term outcomes. Aim To compare early changes in patient-reported outcome measures after 8weeks and long-term response to mepolizumab treatment. Method 22 severe eosinophilic asthma patients starting mepolizumab therapy in a severe asthma centre in the Netherlands were evaluated on baseline, 8weeks and 52weeks, collecting questionnaire scores and asthma-related parameters. Well-controlled asthma was defined as an asthma control questionnaire score ≤ 0.75. Long-term treatment response was defined as continuing mepolizumab therapy at 52weeks. Results Nine patients (41%) had well-controlled asthma at 8weeks and all were mepolizumab responders at 52weeks (positive predictive value = 100%, 95%CI 66-100), versus only 5 responders out of 13 patients with not well-controlled asthma at 8weeks (negative predictive value = 62%, 95%CI 32-86). Conclusion The results in this study suggest that patients receiving mepolizumab therapy with an ACQ-score ≤ 0.75 at 8weeks are unlikely to need extensive monitoring, for they are very likely to be long-term responders.

Post SRS Target Diffusion Metrics for Response Prognostication in Idiopathic Trigeminal Neuralgia

Diffusion tensor imaging (DTI) is used to measure the movement of water molecules in biological tissue, which permits a thorough characterization of white matter microstructure through quantitative diffusivity metrics. The most commonly used diffusivity metric, fractional anisotropy (FA), provides insight into the overall white matter microstructural properties, whereas radial diffusivity (RD), axial diffusivity (AD), and mean diffusivity (MD) suggest changes in myelination, axonal integrity & underlying neuro-inflammation and edema respectively. Study purpose is to find whether trigeminal nerve diffusivity metrics at a single, early time point after frameless SRS is predictive of long-term pain relief in patients with TN.Study cohort comprised of 44 pts with inclusion criteria were: 1) diagnosis of classic, type 1 TN 2) SRS treatment with no prior surgical procedures for TN; 3) 3 tesla MRI scans at 6 months posttreatment (range 5-7 months); and 4) at least 12 months of clinical follow-up. Patients with TN secondary to multiple sclerosis, cranial tumors, or vertebrobasilar dolichoectasia compressing the brainstem were excluded from the study. For each patient, diffusivity metrics (FA, MD, RD, and AD) were extracted from both the affected and unaffected trigeminal nerves at 6 months posttreatment 6 months diffusivity metrics were compared with long-term clinical outcome. Patients were identified as long-term responders if they achieved at least 75% reduction in preoperative pain for 12 months or longer following SRS. Average microstructural diffusivity differences (within group - pre and post treatment; across group - responder & non-responders) were analyzed using paired / Independent T test.Trigeminal nerve diffusivity at 6 months post-SRS was predictive of long-term clinical effectiveness, where long-term responders (n = 36) showed significantly lower fractional anisotropy at the radiosurgical target of their affected nerve compared to their contralateral, unaffected nerve and to nonresponders. Radial diffusivity and mean diffusivity, correlates of myelin alterations and inflammation, were also significantly higher in the affected nerve of long-term responders compared to their unaffected nerve. Nonresponders (n = 8) did not exhibit any characteristic diffusivity changes after SRS.DTI, FA specifically, appears to be a strong, objective measure to assess the effects of radiation on a nerve. Incorporating early DTI assessment can provide prognostic information that supplements clinical measures.

Tre-P-07 - Patient characteristics of long-term responders to mogamulizumab: results from the MAVORIC study

Background: The MAVORIC phase 3, randomized trial, compared safety and efficacy of mogamulizumab (Moga) with vorinostat (Vori) in patients (pts) with relapsed/refractory mycosis fungoides (MF) or Sézary syndrome (SS). Among Moga-treated pts, global overall response rate (ORR) was 28% (52/186), with median duration of response (DOR) of 14.1 months (mo). This analysis assessed the clinical and demographic characteristics of MAVORIC cohorts with varying ORR durations.