Subgroup analysis of rucaparib versus chemotherapy as treatment for BRCA-mutated, advanced, relapsed ovarian carcinoma: Effect of platinum sensitivity in the randomized, phase 3 study ARIEL4

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Background: In ARIEL4 (NCT02855944), rucaparib significantly improved the primary endpoint of progression-free survival (PFS) vs chemotherapy (CT) in patients with advanced, relapsed ovarian carcinoma (OC) harboring a deleterious BRCA1/2 (BRCA) mutation (median PFS 7.4 [95% CI 7.3–9.1] vs 5.7 [5.5–7.3] months; hazard ratio (HR) 0.64 [95% CI 0.49–0.84]; P=0.001). This prespecified exploratory analysis investigated the effect of platinum sensitivity on the efficacy of rucaparib vs CT in ARIEL4. Methods: Patients were randomized 2:1 to oral rucaparib 600 mg twice daily or CT and stratified based on progression-free interval (≥1 to <6 months = platinum resistant; ≥6 to <12 months = partially platinum sensitive; ≥12 months = fully platinum sensitive). In the CT group, patients with platinum-resistant or partially platinum-sensitive disease received weekly paclitaxel 60–80 mg/m2; patients with fully platinum-sensitive disease received investigator’s choice of platinum-based CT (single-agent carboplatin or cisplatin, or platinum doublet). Patients could crossover from CT to rucaparib following radiologic disease progression. Efficacy endpoints were explored in patients with a confirmed BRCA mutation (patients with a reversion mutation were excluded), based on the randomization strata of platinum sensitivity. Results: The visit cutoff date was September 30, 2020. PFS and objective response rates (ORR) per RECIST v1.1 for rucaparib vs CT across subgroups are presented in the Table. The most common treatment-emergent adverse events in the rucaparib group were anemia/decreased hemoglobin (platinum-resistant patients: rucaparib 47% vs CT 40%; partially platinum-sensitive patients: 63% vs 27%; fully platinum-sensitive patients: 58% vs 20%) and nausea (52% vs 21%; 51% vs 23%; 60% vs 68%). In the intent-to-treat population, 74/116 (64%) patients in the CT group crossed over to receive rucaparib: 39/59 (66%) with platinum-resistant, 25/31 (81%) with partially platinum-sensitive, and 10/26 (38%) with fully platinum-sensitive disease. Conclusions: Results from this exploratory subgroup analysis suggest that rucaparib is a reasonable treatment option for heavily pretreated patients across all platinum sensitivity subgroups. Safety was consistent with prior rucaparib studies. Clinical trial information: NCT02855944. [Table: see text]

Final results from the KEYNOTE-100 trial of pembrolizumab in patients with advanced recurrent ovarian cancer

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Background: Pembrolizumab (pembro) showed modest clinical activity in patients (pts) with recurrent advanced ovarian cancer (AOC) after a median follow-up of 16.9 mo in an interim analysis of KEYNOTE-100 (NCT02674061). We present the protocol-specified final analysis based on a data cutoff of 18-SEP-2019. Methods: Key eligibility criteria included epithelial ovarian, fallopian tube, or primary peritoneal cancer, confirmed recurrence following front-line platinum-based therapy, ECOG PS 0-1, and provision of a tumor sample for biomarker analysis. Pts in cohort A received ≤2 prior chemotherapy lines for recurrent AOC and had a platinum-free or treatment-free interval (PFI/TFI) of ≥3 to 12 mo. Pts in cohort B received 3-5 prior chemotherapy lines and had a PFI/TFI of ≥3 mo. Pts received pembro 200 mg Q3W for 2 yr or until progression, death, or unacceptable toxicity. Tumor imaging was performed every 9 wk for 1 yr and every 12 wk thereafter. Primary study endpoint was ORR per RECIST v1.1 by independent central review in both cohorts and by tumor PD-L1 expression using the combined positive score (CPS). Secondary endpoints included DOR, DCR (CR+PR+SD≥24 wk), PFS, OS, and safety. Results: 376 pts were enrolled and treated, 285 in cohort A and 91 in cohort B. Median age (range) was 61 (25 to 89) yr, 64.4% had ECOG PS 0, and 75.3% had high grade serous disease. In cohorts A and B, ORR (95% CI) was 8.1% (5.2, 11.9) and 9.9% (4.6, 17.9) in the total population, 6.9% (2.8, 13.8) and 10.2% (3.4, 22.2) in pts with CPS ≥1, and 11.6% (3.9, 25.1) and 18.2% (5.2, 40.3) in pts with CPS ≥10. Median DOR (range) was 8.3 (3.9 to 35.4+) mo in cohort A and 23.6 (3.3+ to 32.8+) mo in cohort B. DCR (95% CI) was 22.1% (17.4, 27.4) and 22.0% (14.0, 31.9). Median PFS was 2.1 mo in both cohorts. In cohorts A and B, median OS was 18.7 mo (17.0, 22.5) and 17.6 mo (13.3, 24.4) in the total population, 20.6 mo (15.2, 23.2) and 20.7 mo (13.6, 27.4) in pts with CPS ≥1, and 21.9 mo (12.9, 26.8) and 24.0 mo (14.5, NR) in pts with CPS ≥10. 73.7% of pts had treatment-related AEs and 20.2% were grades 3-4. There were 2 treatment-related deaths (Stevens-Johnson syndrome and hypoaldosteronism). Immune-mediated AEs occurred in 23.7% of pts. Conclusions: Pembro monotherapy was associated with modest antitumor activity in pts with recurrent AOC. There appeared to be a trend toward increased ORR with higher PD-L1 expression in both cohorts. Responses were durable and typically lasted ≥6 months. Median OS was 18.7 months overall, with a trend toward a longer OS with increasing PD-L1 expression in both cohorts. No new safety signals were identified. Clinical trial information: NCT02674061.

Final overall survival (OS) results from SOLO2/ENGOT-ov21: A phase III trial assessing maintenance olaparib in patients (pts) with platinum-sensitive, relapsed ovarian cancer and a BRCA mutation

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Background: SOLO2 (ENGOT ov-21; NCT01874353) showed that maintenance therapy with the PARP inhibitor olaparib in pts with platinum-sensitive relapsed ovarian cancer (PSROC) and a BRCA mutation (BRCAm) led to a statistically significant improvement in median progression-free survival (PFS) of 13.6 months vs placebo (hazard ratio [HR] 0.30). Time to second progression or death significantly improved (Pujade-Lauraine et al Lancet Oncol 2017) and a quality-adjusted PFS benefit was seen (Friedlander et al Lancet Oncol 2018) with maintenance olaparib vs placebo. We report the preplanned final OS analysis for SOLO2. Methods: Pts with PSROC and a BRCAm who had received ≥2 lines of treatment and were in response to their most recent platinum-based chemotherapy received maintenance olaparib (300 mg bid tablets) or placebo. Pts were stratified by response to previous chemotherapy (complete vs partial) and length of platinum-free interval (>6–12 months vs >12 months). OS was a secondary endpoint. The only preplanned OS sensitivity analysis was an OS analysis in the Myriad germline BRCAm subset (Myriad BRAC Analysis test). Results: At final data cut-off (Feb 3, 2020), median follow-up was 65 months in both treatment arms. A long-term treatment benefit was seen with olaparib vs placebo with an OS HR of 0.74 (95% confidence interval [CI] 0.54–1.00) in the full analysis set (FAS; unadjusted for crossover; 38.4% of placebo pts crossed over to a PARP inhibitor) (Table). At 5 years: by Kaplan-Meier estimates, 28.3% of pts in the olaparib arm vs 12.8% of pts in the placebo arm were alive and had still not received subsequent treatment; 42.1% of olaparib pts vs 33.2% of placebo pts were alive. The long-term tolerability profile of olaparib was generally consistent with that reported previously. Conclusions: In the final analysis of SOLO2, maintenance olaparib provided an unprecedented improvement of 12.9 months in median OS vs placebo. This is the first study with olaparib tablets, and the first since Study 19 (NCT00753545), to provide long-term follow-up and final OS data in pts with PSROC and a BRCAm. Clinical trial information: NCT01874353. [Table: see text]

Results of a completed first-in-human phase Ib dose-escalation study of oral CBL0137 in patients with advanced solid tumors

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Background: Curaxin CBL0137 is a novel compound with broad anticancer activity in animal models. The drug is a non-genotoxic DNA intercalator that interferes with histone/DNA binding causing decondensation of chromatin in tumor cells, functional inactivation of histone chaperone FACT, activation of p53 and IFN responses, and inhibition of pro-cancer transcriptional factors, MYC, NF-kB, HSF1, and HIF1a. Methods: The study enrolled adults with advanced chemorefractory solid tumors, ECOG PS ≤2, and adequate organ function. The primary objective was to find the maximum tolerated dose (MTD) and recommended dosing regimen (RDR). Secondary objectives were to evaluate CBL0137 safety, pharmacokinetics, and efficacy. CBL1037 was given orally once daily (QD) for the first 14 days of repeated 28-day cycles. A 3+3 dose escalation determined the MTD, defined as the highest dose at which ≤1 of 6 pts had Cycle 1 dose-limiting toxicity (DLT). Pharmacokinetics were assessed on Days 1 and 13. Efficacy was evaluated every 8 weeks. Results: 60 pts were enrolled (females/males [n]: 42/18; median [range] age 56 [25-76] years; ECOG PS [n] 0/1/2: 8/49/3); cancer types [n]: ovarian cancer [15], colorectal cancer [14], breast cancer [11], others [20]) over 16 dose levels ranging from 4 mg to 200 mg QD. Durations of therapy ranged from 6 to 342 days. Three DLTs were observed: prolongation of QTc Gr 3 (88 mg QD), neutropenia/thrombocytopenia Gr 4 (200 mg QD), and LV dysfunction Gr 3 (200 mg QD). Dose-dependent nausea/vomiting was observed and was Gr 2-4 at 200 mg QD. Gr 1/2 photosensitization occurred in 11 subjects across doses from 48 to 200 mg QD but was successfully managed with sun protection and resulted in no dose modifications or discontinuations. On Day 1, mean (range) plasma CBL0137 Tmax values were 5.1 (1-10) hrs. Generally linear increases in AUC occurred with increasing CBL0137 dose. Mean (range) t1/2 values were 25.6 (0.3-166) hrs, with minor dose dependency. Mean (range) Day 13/Day 1 Ctrough ratios showed 3.6 (1.7-7.2)-fold accumulations. Disease control was registered in 11 pts who had stable disease (SD). Target lesion regressions up to 21% were documented in 4 patients with breast cancer (2), sarcoma (1), and ovarian cancer (1). Pts with breast cancer (1) and sarcoma (1) had SD for > 36 weeks. Conclusions: The Phase 2 RDR for oral CBL0137 was established as 180 mg QD x 14 days in 28-day cycles based on bone marrow and gastrointestinal DLTs at 200 mg QD. CBL0137 showed a manageable safety profile with efficacy signals. Further study as a component of combinations is planned. Clinical trial information: 847 .

A randomized phase III trial in patients with recurrent platinum sensitive ovarian cancer comparing efficacy and safety of paclitaxel micellar and Cremophor EL-paclitaxel

OBJECTIVE

Paclitaxel micellar was developed to avoid Cremophor-EL (Cr-EL) associated dose limiting toxicity and to allow a shorter infusion time. The efficacy and safety of paclitaxel micellar (+carboplatin) was compared to Cr-EL paclitaxel (+carboplatin) in recurrent platinum-sensitive ovarian, fallopian tube or peritoneal carcinoma.

METHODS

This was a multicentre, open-label, randomized phase III trial. Adult patients with recurrent disease was assigned to six 3-week cycles of paclitaxel micellar (250 mg/m²) administered as 1-h infusion or Cr-EL paclitaxel (175 mg/m²) as 3-h infusion. Both arms received carboplatin (AUC 5-6). Primary objective was non-inferiority for progression free survival (PFS) using computed tomography scans. Overall survival (OS) was included as secondary endpoint.

RESULTS

Between 2009 and 2013, 789 patients were randomized to receive experimental (N = 397) or control (N = 392) treatment. PFS for paclitaxel micellar was non-inferior to Cr-EL paclitaxel with a hazard ratio of 0.86 (95% CI: 0.72;1.03) in the per protocol population (PP), favouring paclitaxel micellar (non-inferiority margin was 1.2). Non-inferiority of OS was shown in the PP population with a hazard ratio of 0.95 (95% CI: 0.78; 1.16), favouring paclitaxel micellar (non-inferiority margin was 1.185). The most common adverse event was neutropenia (grade ≥ 3); 245 patients (79%) for paclitaxel micellar vs 213 patients (66%) for Cr-EL paclitaxel. The frequency of peripheral sensory neuropathy (any grade) was similar between the arms; 16% for paclitaxel micellar and 20% for Cr-EL paclitaxel.

CONCLUSION

Paclitaxel micellar (+ carboplatin) is non-inferior to Cr-EL paclitaxel (+ carboplatin) in terms of PFS and OS in the studied population. It provides a treatment option of a higher paclitaxel dose with a shorter infusion time without mandatory premedication.

TRIAL REGISTRATION NUMBER

2008-002668-32 (EudraCT), NCT00989131 (ClinicalTrials.gov).

Antitumor activity and safety of pembrolizumab in patients with advanced recurrent ovarian cancer: results from the phase II KEYNOTE-100 study

BACKGROUND

Advanced recurrent ovarian cancer (ROC) is the leading cause of gynecologic cancer-related death in developed countries and new treatments are needed. Previous studies of immune checkpoint blockade showed low objective response rates (ORR) in ROC with no identified predictive biomarker.

PATIENTS AND METHODS

This phase II study of pembrolizumab (NCT02674061) examined two patient cohorts with ROC: cohort A received one to three prior lines of treatment with a platinum-free interval (PFI) or treatment-free interval (TFI) between 3 and 12 months and cohort B received four to six prior lines with a PFI/TFI of ≥3 months. Pembrolizumab 200 mg was administered intravenously every 3 weeks until cancer progression, toxicity, or completion of 2 years. Primary end points were ORR by Response Evaluation Criteria in Solid Tumors version 1.1 per blinded independent central review by cohort and by PD-L1 expression measured as combined positive score (CPS). Secondary end points included duration of response (DOR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

Cohort A enrolled 285 patients; the first 100 served as the training set for PD-L1 biomarker analysis. Cohort B enrolled 91 patients. ORR was 7.4% for cohort A and 9.9% for cohort B. Median DOR was 8.2 months for cohort A and not reached for cohort B. DCR was 37.2% and 37.4%, respectively, in cohorts A and B. Based on the training set analysis, CPS 1 and 10 were selected for evaluation in the confirmation set. In the confirmation set, ORR was 4.1% for CPS <1, 5.7% CPS ≥1, and 10.0% for CPS ≥10. PFS was 2.1 months for both cohorts. Median OS was not reached for cohort A and was 17.6 months for cohort B. Toxicities were consistent with other single-agent pembrolizumab trials.

CONCLUSIONS

Single-agent pembrolizumab showed modest activity in patients with ROC. Higher PD-L1 expression was correlated with higher response.

CLINICAL TRIAL NUMBER

Clinicaltrials.gov, NCT02674061.

Efficacy of maintenance olaparib for newly diagnosed, advanced ovarian cancer patients (pts) by BRCA1 or BRCA2 mutation in the phase III SOLO1 trial

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Background: In SOLO1 (NCT01844986), maintenance olaparib resulted in a significant improvement in progression-free survival (PFS) for newly diagnosed, BRCA1- and/or BRCA2-mutated, advanced ovarian cancer pts compared with placebo (HR 0.30, 95% CI 0.23–0.41; median not reached vs 13.8 months; Moore et al. N Engl J Med 2018). We investigated PFS in SOLO1 for the subgroups of pts with BRCA1 mutations ( BRCA1m) or BRCA2 mutations ( BRCA2m). Methods: All pts were in clinical complete or partial response to platinum-based chemotherapy and were randomized to maintenance olaparib (300 mg twice daily; tablets) or placebo. After 2 years, pts with no evidence of disease discontinued study treatment, but pts with evidence of disease could continue study treatment. PFS by BRCAm was a predefined analysis. BRCAm were identified by central germline (Myriad or BGI) or local testing; Foundation Medicine testing confirmed tumor BRCAm. Results: Median follow-up for PFS was ~41 months in the olaparib and placebo arms. Of 391 randomized pts, 282 had BRCA1m (72%), 106 had BRCA2m (27%) and three (1%) had both (Table). Two pts in the olaparib arm had somatic BRCAm (one BRCA1m, one BRCA2m); all others had germline BRCAm. At the primary data cut-off, 155 pts in the BRCA1-mutated group (55%), 43 in the BRCA2-mutated group (41%) and none in the BRCA1/2 -mutated group had disease progression. The percentage of BRCA1-mutated pts who received olaparib and were progression-free at 1, 2 and 3 years was 86%, 69% and 53% (vs 52%, 36% and 26% receiving placebo) and for BRCA2-mutated pts was 92%, 85% and 80% (vs 50%, 32% and 29%, respectively). Conclusions: Significant PFS benefit with olaparib versus placebo was demonstrated for all pts, regardless of whether they had BRCA1m or BRCA2m. Statistical tests were not used to compare BRCA1- and BRCA2-mutated pts, but those with BRCA2m appeared to receive greater benefit from maintenance olaparib than those with BRCA1m. Clinical trial information: NCT01844986. [Table: see text]

Non-interventional study OVATAR final report: Diagnostic and treatment approaches in Russian ovarian cancer population—BRCAm group analysis

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Background: First large Russian ovarian cancer observational study was conducted in 2014-2018. Methods: A total of 500 patients in 29 sites in Russia with newly diagnosed ovarian, peritoneal and fallopian tube cancer was enrolled (NCT02122588). The primary objective was to describe treatment approaches in the first line treatment. 141 patients (pts) with BRCA1/2 mutations (BRCA1/2mt) detected by NGS in blood and tissue were observed prospectively during at least 2 years. Results: Rate of BRCA1/2 mutations in Russian population is high – 28.4% (141 from 496 available for any testing). 77.6% (388/500) underwent biomarkers blood testing prior to treatment. CA-125 was positive in 99.7% (387/388), 15.2% (59/388) of pts had positive CA19-9, CA72-4 - in 2.3% (9/388). Positive CEA was presented in 15.2% (59/388). This marker was detected more frequently in BRCA2mt pts subgroup (28.0% (7/25)) than in BRCA1mt pts: 9.0% (8/90) (p = 0.05). 26.6% (133/500) of all study population had an oncology family history; 44.0% (62/141) BRCA1/2mt pts had relatives with oncological diseases and 19.7% (70/355) in BRCA wild type pts (p = 0.0001). 98.6% (139/141) of BRCA1/2mt pts received first line therapy. Objective response rate was registered in 79.8% (111/139) pts. Progression after platinum based regimens was observed in 53.6% (59/110) BRCA1mt pts and 44.8% (13/29) BRCA2mt pts. 35.6 % (21/59) of BRCA1mt pts had platinum-refractory and platinum-resistant relapses, while 15.4% in BRCA2mt subgroup (2/13) (p = 0.64). Platinum-sensitive relapses were in 64.4% (38/59) BRCA1mt pts and 84.6% BRCA2mt (11/13) (p = 0,64). Median PFS in BRCA1/2mt pts was 25.5 months. Among BRCA1/2mt pts underwent cytoreduction median PFS in subgroup without visible residual tumor was 36.4 months and in subgroup with residual tumor < 1 cm 15.3 months. Conclusions: In this large-scale prospective non-interventional study diagnostics and treatment approaches in Russian ovarian cancer pts were evaluated and high frequency of BRCA1/2mt was observed. Pts with BRCA1/2mt had better prognosis and most of them had platinum-sensitive relapses after first line chemotherapy that allowed platinum-based regimen rechallenge.

Adverse events (AEs) with maintenance olaparib in newly diagnosed patients (pts) with advanced ovarian cancer (OC) and a BRCA mutation (BRCAm): Phase III SOLO1 trial

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Background: In SOLO1 (NCT01844986), maintenance olaparib provided a substantial progression-free survival benefit vs placebo in newly diagnosed pts with advanced OC, a BRCAm and clinical complete or partial response to platinum therapy (HR 0.30; 95% CI 0.23–0.41) and was well tolerated (Moore et al. NEJM 2018). We analysed the most common AEs and hematologic AEs in SOLO1. Methods: Pts received olaparib tablets 300 mg twice daily or placebo until progression unless they had no evidence of disease at 2 years, in which case treatment stopped. AEs were graded using CTCAE v4.0. Results: Of 391 pts randomized, 390 (olaparib, 260; placebo, 130) were treated and included in the safety analysis. Median treatment duration was approximately 25 months for olaparib vs 14 for placebo. Median time to first onset of the most common AEs (nausea, vomiting, fatigue/asthenia, anemia) and neutropenia and thrombocytopenia was < 3 months; the first event lasted a median of < 2 months, apart from fatigue/asthenia, which lasted a median of < 4 months (Table). AEs were usually managed with supportive therapy and/or dose modification; few pts discontinued. Conclusions: AEs in newly diagnosed pts with advanced OC treated with olaparib usually occurred early and were manageable, with few discontinuations. Clinical trial information: NCT01844986. [Table: see text]

Maintenance olaparib after platinum-based chemotherapy in patients (pts) with newly diagnosed advanced ovarian cancer (OC) and a BRCA mutation (BRCAm): Efficacy by surgical and tumor status in the Phase III SOLO1 trial

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Background: In SOLO1 (NCT01844986), maintenance olaparib significantly improved progression-free survival (PFS) vs placebo (HR 0.30; 95% CI 0.23–0.41; Moore et al. N Engl J Med 2018) in pts with newly diagnosed advanced OC and a BRCAm. This analysis evaluates olaparib efficacy by timing of surgery, presence of residual tumor following surgery and response status after completion of chemotherapy in SOLO1. Methods: Pts underwent cytoreductive surgery and were in clinical complete response (CR) or partial response (PR) after platinum-based chemotherapy. Pts were stratified by response and received olaparib tablets 300 mg twice daily or placebo. Investigator-assessed PFS and objective response were assessed using modified RECIST v1.1. Results: 260 pts were randomized to olaparib and 131 to placebo; one pt did not receive placebo. Median follow-up was 41 months in both arms. 63% and 35% of pts underwent upfront and interval surgery, 21% and 76% had residual and no residual macroscopic disease after surgery, and 74% and 26% entered the study in clinical CR and PR (based on electronic case report form [eCRF] data). PFS was significantly improved regardless of the timing of surgery, residual disease status after surgery or response after platinum-based chemotherapy (Table). In pts with baseline radiologic evidence of disease (n=80; eCRF), the objective response rate was 43% for olaparib (CR, 28%) and 23% for placebo (CR, 12%). Conclusions: Maintenance olaparib improved outcomes compared with placebo in pts with newly diagnosed advanced OC and a BRCAm, regardless of surgical or tumor status. Clinical trial information: NCT01844986. [Table: see text]

[Case of restoration of reproductive function using the method of cryopreservation and autotransplantation of ovarian tissue in a Hodgkin's lymphoma patient]

Recent advances of cancer treatment resulted in the increase of patient survival rate. Treatment for Hodgkin’s lymphoma (HL) may impair reproductive function, which leads to a decrease of the quality of life of cancer survival. Today different approaches have been developed for fertility preservation, one of which is the cryopreservation of ovarian tissue with subsequent orthotopic transplantation. We have described a recovery of reproductive function in patient of 28 years with acute ovarian failure, which was induced after cancer treatment. After the orthotopic transplantation cryopreserved ovarian tissue ongoing pregnancy was achieved in the natural cycle after IVF insemination. We have described the first live birth in Russia after the orthotopic transplantation cryopreserved ovarian tissue in cancer patient. This approach has resulted in the recovery of endocrine function without replacement hormonal therapy and possibility for a woman to have her own biological baby. It suggests that cryopreservation of ovarian tissue should be offered to all young women diagnosed with cancer.