FDA Approval Summary: Enfortumab Vedotin Plus Pembrolizumab for Locally Advanced or Metastatic Urothelial Carcinoma.

On December 15, 2023, the FDA granted traditional approval to enfortumab vedotin-ejfv plus pembrolizumab (EV + Pembro) for patients with locally advanced or metastatic urothelial carcinoma (la/mUC). Substantial evidence of effectiveness was obtained from EV-302/KEYNOTE-A39 (NCT04223856), an open-label, randomized, trial evaluating EV + Pembro versus cisplatin or carboplatin plus gemcitabine (Plat + Gem) in patients with previously untreated la/mUC. A total of 886 patients were randomized (1:1) to receive EV 1.25 mg/kg intravenously on days 1 and 8 of each 21-day cycle until disease progression or unacceptable toxicity plus pembrolizumab 200 mg intravenously on day 1 of each 21-day cycle for up to 35 cycles, or Plat + Gem for up to 6 cycles. Dual primary endpoints were progression-free survival (PFS) determined by blinded independent central review and overall survival (OS). Median PFS was 12.5 months (95% CI: 10.4, 16.6) in the EV + Pembro arm and 6.3 months (95% CI: 6.2, 6.5) in the Plat + Gem arm (HR 0.450 [95% CI: 0.377, 0.538]; p-value < 0.0001). Median OS was 31.5 months (95% CI: 25.4, NE) in the EV + Pembro arm and 16.1 months (95% CI: 13.9, 18.3) in the Plat + Gem arm (HR 0.468 [95% CI: 0.376, 0.582]; p-value < 0.0001). The safety profile of EV + pembrolizumab was similar to that observed in EV-103/KEYNOTE-869 in cisplatin-ineligible patients with la/mUC. This article summarizes the data and the FDA thought process supporting traditional approval of EV + pembrolizumab, as well as additional exploratory analyses conducted by FDA.

US Food and Drug Administration Approval Summary: Capivasertib With Fulvestrant for Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Locally Advanced or Metastatic Breast Cancer With PIK3CA/AKT1/PTEN Alterations.

PURPOSE: The US Food and Drug Administration (FDA) approved capivasertib in combination with fulvestrant for adult patients with hormone receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative, locally advanced, or metastatic breast cancer (MBC) who have received at least one previous endocrine therapy and whose tumors harbor one or more phosphatidylinositol 3-kinase (PIK3CA)/AKT Serine/Threonine Kinase 1 (AKT1)/phosphatase and tensin homolog (PTEN) alterations, as detected by an FDA-approved test. PATIENTS AND METHODS: Approval was based on CAPItello-291, a randomized, double-blind, multicenter trial of 708 patients with hormone receptor-positive, HER2-negative advanced or MBC, including 289 patients with PIK3CA/AKT1/PTEN tumor alterations. Patients were randomly assigned 1:1 to receive capivasertib 400 mg twice daily for 4 days per week with fulvestrant versus placebo with fulvestrant. Random assignment was stratified by presence of liver metastases, previous treatment with CDK4/6i, cyclin-dependent kinase four and six (CDK4/6) inhibitors, and geographical region. RESULTS: A statistically significant progression-free survival (PFS) benefit was demonstrated in the overall population (hazard ratio [HR], 0.6 [95% CI, 0.51 to 0.71]); this result was driven by 289 patients in the biomarker-positive population (HR, 0.5 [95% CI, 0.37 to 0.68]). An exploratory analysis of investigator-assessed PFS in the 313 (44%) patients in the biomarker-negative population showed uncertain benefit (HR, 0.78 [95% CI, 0.60 to 1.01]). With capivasertib, more patients had Grade ≥3 toxicities. Key concerns included hyperglycemia (18% all-grade, 2.8% Grade ≥3), cutaneous toxicity (58% all-grade, 17% Grade ≥3), and diarrhea (72% all-grade, 9% Grade ≥3). CONCLUSION: Capivasertib with fulvestrant was approved for patients whose tumors harbored PIK3CA/AKT1/PTEN alterations. Benefit-risk assessment in this subgroup was favorable based on a statistically significant and clinically meaningful improvement in PFS in the context of an acceptable safety profile including no evidence of a potential detriment in overall survival. By contrast, the benefit-risk was unfavorable in the biomarker-negative population.

FDA Approval Summary: Durvalumab and Pembrolizumab, Immune Checkpoint Inhibitors for the Treatment of Biliary Tract Cancer.

On September 2, 2022, the Food and Drug Administration (FDA) approved durvalumab in combination with cisplatin and gemcitabine, for the treatment of patients with unresectable or metastatic biliary tract cancers (BTC). On October 31, 2023, the FDA approved pembrolizumab in combination with cisplatin and gemcitabine for the same indication. Approvals were based on two randomized, multiregional, placebo-controlled trials that randomly allocated patients to receive durvalumab (TOPAZ-1) or pembrolizumab (KEYNOTE-966) in combination with chemotherapy or placebo in combination with chemotherapy. Overall survival (OS) was the primary endpoint in both studies. In both studies, a statistically significant and clinically meaningful improvement in OS was demonstrated. In the TOPAZ-1 trial, the median OS of patients receiving durvalumab was 12.8 months [95% confidence interval (CI), 11.1-14.0] and 11.5 months (95% CI, 10.1-12.5) in patients receiving placebo [hazard ratio (HR), 0.80 (95% CI, 0.66-0.97)]. In the KEYNOTE-966 trial, the median OS of patients receiving pembrolizumab was 12.7 months (95% CI, 11.5-13.6) and 10.9 months (95% CI, 9.9-11.6) in patients receiving placebo [HR, 0.83 (95% CI, 0.72-0.95)]. The addition of checkpoint inhibitors to standard of care chemotherapy for this indication did not reveal any new adverse event signals, and the safety profile was generally consistent with the known clinical experience with durvalumab, pembrolizumab, and the backbone chemotherapy regimen. The approvals of durvalumab and pembrolizumab in combination with standard of care cisplatin and gemcitabine for the treatment of unresectable or metastatic BTC add two new therapeutic options for these patients.

FDA Approval Summary: Fruquintinib for the Treatment of Refractory Metastatic Colorectal Cancer.

On November 8, 2023, the FDA approved fruquintinib, an inhibitor of vascular endothelial growth factor receptor (VEGFR)-1, -2, and -3, for the treatment of patients with metastatic colorectal cancer (mCRC) who have been previously treated with fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapy, an anti-VEGF therapy, and if RAS wild-type and medically appropriate, an anti-EGFR therapy. Approval was based on Study FRESCO-2, a globally conducted, double-blind, placebo-controlled randomized trial. The primary endpoint was overall survival (OS). The key secondary endpoint was progression-free survival. A total of 691 patients were randomly assigned (461 and 230 into the fruquintinib and placebo arms, respectively). Fruquintinib provided a statistically significant improvement in OS with a hazard ratio (HR) of 0.66 [95% confidence interval (CI), 0.55, 0.80; P < 0.001]. The median OS was 7.4 months (95% CI, 6.7, 8.2) in the fruquintinib arm and 4.8 months (95% CI, 4.0, 5.8) for the placebo arm. Adverse events observed were generally consistent with the known safety profile associated with the inhibition of VEGFR. The results of FRESCO-2 were supported by the FRESCO study, a double-blind, single-country, placebo-controlled, randomized trial in patients with refractory mCRC who have been previously treated with fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapy. In FRESCO, the OS HR was 0.65 (95% CI, 0.51, 0.83; P < 0.001). FDA concluded that the totality of the evidence from FRESCO-2 and FRESCO supported an indication for patients with mCRC with prior treatment with fluoropyrimidine, oxaliplatin-, and irinotecan-based chemotherapy, an anti-VEGF biological therapy, and if RAS wild-type and medically appropriate, an anti-EGFR therapy.

FDA Approval Summary: Enfortumab Vedotin plus Pembrolizumab for Cisplatin-Ineligible Locally Advanced or Metastatic Urothelial Carcinoma.

On April 3, 2023, the FDA granted accelerated approval to enfortumab vedotin-ejfv (EV) plus pembrolizumab for treatment of patients with locally advanced or metastatic urothelial carcinoma who are ineligible for cisplatin-containing chemotherapy. Substantial evidence of effectiveness was obtained from EV-103/KEYNOTE-869 (NCT03288545), a multicohort study. Across cohorts, a total of 121 patients received EV 1.25 mg/kg (maximum of 125 mg) intravenously on days 1 and 8 of a 21-day cycle plus pembrolizumab 200 mg intravenously on day 1 of each 21-day cycle until disease progression or unacceptable toxicity. The major efficacy outcome measures were objective response rate (ORR) and duration of response (DoR), determined by blinded independent central review using RECIST v1.1. The confirmed ORR in 121 patients was 68% (95% confidence interval, 59-76), including 12% with complete responses. The median DoR for the 82 responders was 22 months (range: 1+ to 46+). The safety profile of the combination comprised adverse reactions expected to occur with the corresponding monotherapies, but with overall increased frequency of adverse reactions, including skin toxicity, pneumonitis, and peripheral neuropathy. The article summarizes the data and the FDA thought process supporting accelerated approval of EV + pembrolizumab, as well as additional exploratory analyses conducted by the FDA.

Efficacy of Poly(ADP-ribose) Polymerase Inhibitors by Individual Genes in Homologous Recombination Repair Gene-Mutated Metastatic Castration-Resistant Prostate Cancer: A US Food and Drug Administration Pooled Analysis.

PURPOSE: We performed a pooled analysis of multiple trials of poly(ADP-ribose) polymerase inhibitors (PARPi) in metastatic castration-resistant prostate cancer (mCRPC) to investigate the efficacy of PARPi in each individual homologous recombination repair (HRR) mutated (m) gene. PATIENTS AND METHODS: We pooled patient-level data from trials of PARPi in mCRPC that reported mutation status in individual HRR genes. Any HRR gene with available data across all the randomized trials of PARPi in first-line mCRPC was selected. The hazard ratios (HRs; 95% CI) for radiographic progression-free survival (rPFS; by blinded independent review) and overall survival (OS) of a PARPi plus an androgen receptor pathway inhibitor (ARPI) relative to placebo plus an ARPI in the pool of three randomized trials in first-line mCRPC were calculated using Kaplan-Meier estimates and a Cox proportional hazards model. RESULTS: In ATMm (N = 268), rPFS HR was 1.05 (0.74 to 1.49) and OS HR was 1.18 (0.82 to 1.71). In BRCA1m (N = 64), rPFS HR was 0.51 (0.23 to 1.1) and OS HR was 0.74 (0.34 to 1.61). In BRCA2m (N = 422), rPFS HR was 0.31 (0.23 to 0.42) and OS HR was 0.66 (0.49 to 0.89). In CDK12m (N = 164), rPFS HR was 0.50 (0.32 to 0.80) and OS HR was 0.63 (0.39 to 0.99). In CHEK2m (N = 172), rPFS HR was 1.06 (0.67 to 1.66) and OS HR was 1.53 (0.95 to 2.46). In PALB2m (N = 41) rPFS HR was 0.52 (0.23 to 1.17) and OS HR was 0.78 (0.34 to 1.8). CONCLUSION: In this pooled analysis, benefit from PARPi appeared greatest for patients with BRCA1m, BRCA2m, CDK12m, and PALB2m. Given limitations of this exploratory analysis, the apparent lack of benefit from PARPi in patients with CHEK2m or ATMm should be further explored in future clinical trials.

Cytoreductive nephrectomy in the era of immune checkpoint inhibitors: a US Food and Drug Administration pooled analysis.

BACKGROUND: This pooled analysis of patient-level data from trials evaluated the clinical outcomes of patients with metastatic renal cell carcinoma with or without cytoreductive nephrectomy before a combination of immune checkpoint inhibitor and antiangiogenic therapy. METHODS: Data from 5 trials of immune checkpoint inhibitors plus antiangiogenic therapy were pooled. Only patients with stage 4 disease at initial diagnosis were included to ensure that nephrectomy was performed for cytoreductive purposes and not to previously treat an earlier stage of disease. The effect of cytoreductive nephrectomy before immune checkpoint inhibitor therapy on outcomes was evaluated using the Kaplan-Meier method and a Cox proportional hazards regression model, adjusted for age, sex, risk group, performance status, and the presence of sarcomatoid differentiation. RESULTS: A total of 981 patients were included. The estimated median progression-free survival with and without nephrectomy was 15 and 11 months, respectively; the adjusted hazard ratio was 0.71 (95% confidence interval = 0.59 to 0.85). The estimated median overall survival with and without nephrectomy was 46 and 28 months, respectively; the adjusted hazard ratio was 0.63 (95% confidence interval = 0.51 to 0.77). Objective response was 60% of patients with vs 46% of patients without cytoreductive nephrectomy. CONCLUSIONS: Patients with metastatic renal cell carcinoma who undergo cytoreductive nephrectomy before immune checkpoint inhibitor plus antiangiogenic therapy had improved outcomes compared with patients without cytoreductive nephrectomy. Selection factors for cytoreductive nephrectomy may be prognostic and could not be fully controlled for in this retrospective analysis. Prospective determination of and stratification by prior cytoreductive nephrectomy may be considered when designing clinical trials to assess the impact of this factor on prognosis.

US Food and Drug Administration Approval Summary: Talazoparib in Combination With Enzalutamide for Treatment of Patients With Homologous Recombination Repair Gene-Mutated Metastatic Castration-Resistant Prostate Cancer.

PURPOSE: The US Food and Drug Administration (FDA) approved talazoparib with enzalutamide for first-line treatment of patients with homologous recombination repair (HRR) gene-mutated metastatic castration-resistant prostate cancer (mCRPC). PATIENTS AND METHODS: The approval was based on the HRR gene-mutated (HRRm) population of TALAPRO-2, a randomized, double-blind trial that randomly assigned 1,035 patients with mCRPC to receive enzalutamide with either talazoparib or placebo. Two cohorts enrolled sequentially: an all-comer population (Cohort 1), followed by an HRRm-only population (Cohort 2). The independent primary end points were radiographic progression-free survival (rPFS) per blinded independent central review (BICR) in Cohort 1 (all-comers) and in the combined HRRm population (all HRRm patients from Cohorts 1 and 2). Overall survival (OS) was a key secondary end point. RESULTS: A statistically significant improvement in rPFS by BICR was demonstrated in both the all-comers cohort and the combined HRRm population, with hazard ratio (HR) of 0.63 (95% CI, 0.51 to 0.78; P < .0001) and 0.45 (95% CI, 0.33 to 0.61; P < .0001), respectively. In an exploratory analysis of the 155 patients with BRCA-mutated (BRCAm) mCRPC, rPFS HR was 0.20 (95% CI, 0.11 to 0.36). In the non-HRRm/unknown stratum of Cohort 1 (n = 636), the rPFS HR was 0.70 (95% CI, 0.54 to 0.89). OS was immature. CONCLUSION: Despite a statistically significant rPFS improvement in the all-comer cohort, FDA did not consider the magnitude of rPFS clinically meaningful in the context of the broad indication, combination treatment, and safety profile. Approval was therefore limited to patients with HRRm mCRPC, for whom there was a statistically significant and clinically meaningful improvement in rPFS and favorable OS results. This represents the first approval for the first-line treatment of patients with HRRm mCRPC.

Impact of Increasing PD-L1 Levels on Outcomes to PD-1/PD-L1 Inhibition in Patients With NSCLC: A Pooled Analysis of 11 Prospective Clinical Trials.

BACKGROUND: Programmed death ligand 1 (PD-L1) expression is recognized as a key biomarker in the treatment of non-small cell lung cancer (NSCLC) with anti-PD(L)1 inhibitors. Previous work has highlighted that outcomes in patients with NSCLC treated with anti-PD(L)1 inhibitors generally improve with increasing PD-L1 expression. The objectives of these analyses are to quantitate the effect of PD-L1 expression on outcomes, to characterize the potentially nonlinear relationship between PD-L1 expression and outcomes, and to assess potential differences in these relationships across subgroups. PATIENTS AND METHODS: We performed a retrospective, pooled analysis of 11 clinical trials submitted to the US FDA between 2015 and 2022 that included patients with advanced NSCLC treated with anti-programmed death 1 or anti-PD-L1 immune checkpoint inhibitor (ICI) monotherapy in the first-line (1L) or second-line (2L) treatment setting. The clinical outcomes explored were overall survival (OS), progression-free survival (PFS), and objective response rate (ORR). RESULTS: The primary analysis population included 3806 patients with advanced NSCLC, of which 2040 were treated in 1L and 1766 in 2L. For patients with a PD-L1 score of 100% in the 1L setting, the hazard ratio versus a patient with 1% PD-L1 was 0.55 (95% CI, 0.43 to 0.70) for OS and 0.50 (95% CI, 0.41 to 0.61) for PFS. For patients with a PD-L1 score of 100% in the 2L setting, the hazard ratio versus a patient with 0% PD-L1 was 0.55 (95% CI, 0.43 to 0.71) for OS and 0.51 (95% CI, 0.41 to 0.63) for PFS. Subgroup analyses suggested that this relationship may vary by subgroup, particularly by region. CONCLUSIONS: These analyses suggest PD-L1 expression has an appreciable impact on clinical outcomes for patients with NSCLC treated with ICI. As the impact of PD-L1 expression on outcomes may vary across regions, it is critical that future trials are multiregional and enroll a diverse patient population.

A Pooled Analysis of Treatment-Free Survival in Advanced Renal Cell Carcinoma.

PURPOSE: A clinically meaningful attribute of some immune-oncology (IO) regimens is potential durable clinical benefit during a treatment-free interval. We characterize treatment-free survival (TFS) with and without ongoing toxicity in trials of frontline IO-VEGF tyrosine kinase inhibitor (TKI) combinations in patients with advanced renal cell carcinoma (aRCC). EXPERIMENTAL DESIGN: Individual patient data were pooled by treatment arm from randomized trials submitted to the FDA evaluating IO-TKI combination in treatment-naïve aRCC with at least 30 months of median follow-up. OS, TFS, TFS with and without toxicity, and time to all protocol therapy cessation were assessed. TFS was estimated by 30-month restricted mean times, defined as area between Kaplan-Meier curves for two time-to-event endpoints originating at randomization: time to all protocol therapy cessation and time to subsequent systemic therapy initiation or death. RESULTS: Three trials met criteria for analysis; 1,183 patients received IO-TKI versus 1,184 on control arms receiving TKI alone (sunitinib, SUN). IO-TKI and SUN groups spent 9% {2.7 months [95% confidence interval (CI), 1.8-3.5]} and 10% [2.9 months (95% CI, 2.1-3.8)] of the 30-month period alive and treatment-free, respectively. Mean TFS without grade ≥3 toxicity was 1.7 and 2.3 months in IO-TKI and SUN groups, respectively. CONCLUSIONS: In this post hoc partitioned survival analysis, TFS and TFS without toxicity appeared similar in the IO-TKI group compared with the SUN group. These findings may reflect contin-uation of TKI until progression per protocol design in all trials and discontinuation of IO after 2 years in two trials. See related commentary by Stadler and Karrison, p. 3098.

US Food and Drug Administration Approval Summary: Elacestrant for Estrogen Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative, ESR1-Mutated Advanced or Metastatic Breast Cancer.

PURPOSE: The US Food and Drug Administration (FDA) approved elacestrant for the treatment of postmenopausal women or adult men with estrogen receptor-positive (ER+), human epidermal growth factor receptor 2-negative (HER2-), estrogen receptor 1 (ESR1)-mutated advanced or metastatic breast cancer with disease progression after at least one line of endocrine therapy (ET). PATIENTS AND METHODS: Approval was based on EMERALD (Study RAD1901-308), a randomized, open-label, active-controlled, multicenter trial in 478 patients with ER+, HER2- advanced or metastatic breast cancer, including 228 patients with ESR1 mutations. Patients were randomly assigned (1:1) to receive either elacestrant 345 mg orally once daily (n = 239) or investigator's choice of ET (n = 239). RESULTS: In the ESR1-mut subgroup, EMERALD demonstrated a statistically significant improvement in progression-free survival (PFS) by blinded independent central review assessment (n = 228; hazard ratio [HR], 0.55 [95% CI, 0.39 to 0.77]; P value = .0005). Although the overall survival (OS) end point was not met, there was no trend toward a potential OS detriment (HR, 0.90 [95% CI, 0.63 to 1.30]) in the ESR1-mut subgroup. PFS also reached statistical significance in the intention-to-treat population (ITT, N = 478; HR, 0.70 [95% CI, 0.55 to 0.88]; P value = .0018). However, improvement in PFS in the ITT population was primarily attributed to results from patients in the ESR1-mut subgroup. More patients who received elacestrant experienced nausea, vomiting, and dyslipidemia. CONCLUSION: The approval of elacestrant in ER+, HER2- advanced or metastatic breast cancer was restricted to patients with ESR1 mutations. Benefit-risk assessment in the ESR1-mut subgroup was favorable on the basis of a statistically significant improvement in PFS in the context of an acceptable safety profile including no evidence of a potential detriment in OS. By contrast, the benefit-risk assessment in patients without ESR1 mutations was not favorable. Elacestrant is the first oral estrogen receptor antagonist to receive FDA approval for patients with ESR1 mutations.

FDA Approval Summary: Olaparib in Combination With Abiraterone for Treatment of Patients With BRCA-Mutated Metastatic Castration-Resistant Prostate Cancer.

PURPOSE: This article summarizes the US Food and Drug Administration (FDA) review of the data leading to approval of olaparib plus abiraterone for the treatment of patients with deleterious or suspected deleterious BRCA-mutated (BRCAm) metastatic castration-resistant prostate cancer (mCRPC), as determined by an FDA-approved companion diagnostic test. PATIENTS AND METHODS: Approval was based on the results from PROpel, a double-blind trial that randomly assigned 796 patients with mCRPC to abiraterone plus prednisone or prednisolone with either olaparib or placebo. The primary end point was radiographic progression-free survival (rPFS) per investigator assessment. RESULTS: There was a statistically significant improvement in rPFS for olaparib plus abiraterone versus placebo plus abiraterone, with a median rPFS of 25 versus 17 months and a hazard ratio (HR) of 0.66 (95% CI, 0.54 to 0.81) in the intention-to-treat population. In an exploratory analysis of the subgroup of 85 patients with BRCAm mCRPC, the HR for rPFS was 0.24 (95% CI, 0.12 to 0.45) and the HR for overall survival (OS) was 0.30 (95% CI, 0.15 to 0.59). In an exploratory analysis of the subgroup of 711 patients without an identified BRCA mutation, the HR for rPFS was 0.77 (95% CI, 0.63 to 0.96) and the HR for OS was 0.92 (95% CI, 0.74 to 1.14). Adding olaparib to abiraterone resulted in increased toxicity, including anemia requiring transfusion in 18% of patients. CONCLUSION: In patients with mCRPC, efficacy of the combination of olaparib plus abiraterone was primarily attributed to the treatment effect in the BRCAm subgroup, the indicated population for the approval. For patients without BRCAm, the FDA determined that the modest rPFS improvement, combined with clinically significant toxicities, did not demonstrate a favorable risk/benefit assessment.

FDA Approval Summary: Ribociclib Indicated for Male Patients with Hormone Receptor-Positive, HER2-Negative Advanced or Metastatic Breast Cancer.

On December 10, 2021, the FDA expanded the indications for ribociclib to include male patients for the treatment of hormone receptor-positive, HER2-negative advanced or metastatic breast cancer. Ribociclib is now indicated in combination with an aromatase inhibitor (AI) as initial endocrine-based therapy in adult patients, or with fulvestrant as initial endocrine-based therapy or following disease progression on endocrine therapy (ET), in postmenopausal women or in men. The efficacy of ribociclib + AI for male patients was primarily based on previous favorable benefit-risk assessments of ribociclib from MONALEESA-2 and MONALEESA-7 trials, and supported by COMPLEEMENT-1, an open-label, single-arm, multicenter clinical trial, in which 39 male patients (n = 3,246 total patients) received ribociclib + letrozole + goserelin/leuprolide. The overall response rate (ORR) based on confirmed responses in male patients with measurable disease at baseline was 46.9% [95% confidence interval (CI), 29.1-65.3], consistent with an ORR of 43.6% (95% CI, 41.5-45.8) in the overall population. Overall, adverse reactions occurring in male patients were similar to those occurring in female patients treated with ribociclib + ET. The efficacy of ribociclib + fulvestrant for male patients was primarily based on the previous findings of a favorable benefit-risk assessment from the MONALEESA-3 trial, supported by FDA review of clinical data of a limited number of male patients treated in clinical practice receiving ribociclib + fulvestrant. The known mechanism of action, biologic rationale, and clinical information available adequately demonstrate that the efficacy and safety of ribociclib + AI/fulvestrant are similar in male and female patients. This article summarizes the FDA's decision-making and data supporting the approval of ribociclib in male patients with breast cancer, and discusses regulatory insights.

A U.S. Food and Drug Administration-pooled Analysis of Frontline Combination Treatment Survival Benefits by Risk Groups in Metastatic Renal Cell Carcinoma.

BACKGROUND: While frontline immuno-oncology/tyrosine kinase inhibitor (IO/TKI) combination therapy has established a benefit in metastatic renal cell carcinoma (mRCC), this may differ by International Metastatic RCC Database Consortium (IMDC) risk grouping. Looking at individual trials, we noted an apparently smaller magnitude of benefit for favorable-risk disease. OBJECTIVE: We aimed to assess treatment benefit by risk groupings, especially in favorable-risk, augmenting patient numbers via a pooled analysis. DESIGN, SETTING, AND PARTICIPANTS: We pooled four frontline mRCC trials of IO/TKI combinations including 3,098 patients (839 favorable-risk) with approvals from 2019 to 2021. INTERVENTION: All trials used IO/TKI combinations as the treatment option and sunitinib as the control. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We analyzed progression-free survival (PFS) and overall survival (OS) by IMDC groupings. To specifically address the favorable-risk group, we combined all others into an intermediate/poor-risk group. RESULTS AND LIMITATIONS: In this exploratory analysis adjusted for baseline covariates, IO/TKI combinations have yet to demonstrate an OS benefit in favorable-risk (hazard ratio [HR] 1.24; 95% confidence interval [CI]: 0.86, 1.78) despite demonstrating an OS benefit in the intermediate/poor-risk group (HR 0.64; 95% CI: 0.55, 0.75). In contrast, IO/TKI demonstrated a PFS benefit for both the favorable-risk (HR 0.63; 95% CI: 0.50, 0.79) and the intermediate/poor-risk (HR 0.52; 95% CI: 0.45, 0.60) group. For objective response rate, a smaller difference was observed between the combination and sunitinib arms in favorable-risk (68.2% vs 49.9%) versus intermediate/poor-risk (59.9% vs 36.5%) groups, while the difference in complete response rate was larger for favorable-risk (15.3% vs 6.0%) versus intermediate/poor-risk (9.1% vs 3.4%) groups. CONCLUSIONS: The frontline IO/TKI combination therapy benefit was shown to be greater in the intermediate/poor-risk group than in the favorable-risk group. The OS benefit observed with IO/TKI for mRCC has yet to be demonstrated for favorable-risk patients; longer follow-up is needed. PATIENT SUMMARY: Patients with intermediate/poor-risk metastatic renal cell carcinoma derive an overall survival benefit from immuno-oncology/tyrosine kinase inhibitor combinations, while data for favorable-risk remain immature.

US Food and Drug Administration Approval Summary: Nivolumab Plus Platinum-Doublet Chemotherapy for the Neoadjuvant Treatment of Patients With Resectable Non-Small-Cell Lung Cancer.

PURPOSE: On March 4, 2022, the US Food and Drug Administration (FDA) approved nivolumab plus platinum-doublet chemotherapy for the neoadjuvant treatment of patients with resectable non-small-cell lung cancer (NSCLC). We discuss the FDA's review of the key data and regulatory considerations supporting this approval. PATIENTS AND METHODS: The approval was based on the results of CheckMate 816, an international, multiregional, active-controlled trial that randomly assigned 358 patients with resectable NSCLC, stage IB (≥4 cm) to IIIA (N2) per the American Joint Committee on Cancer seventh staging edition to receive either nivolumab plus platinum-doublet or platinum-doublet chemotherapy alone for three cycles before planned surgical resection. The major efficacy end point that supported this approval was event-free survival (EFS). RESULTS: At the first planned interim analysis (IA), the hazard ratio (HR) for EFS was 0.63 (95% CI, 0.45 to 0.87; P = .0052; statistical significance boundary = .0262) favoring the nivolumab plus chemotherapy arm; the median EFS was 31.6 months (95% CI, 30.2 to not reached) in the nivolumab plus chemotherapy arm versus 20.8 months (95% CI, 14.0 to 26.7) in the chemotherapy-only arm. At the time of a prespecified IA for overall survival (OS), 26% of patients had died, and the HR for OS was 0.57 (95% CI, 0.38 to 0.87; P = .0079; statistical significance boundary = .0033). Eighty-three percent of patients in the nivolumab-containing arm versus 75% in the chemotherapy-only arm received definitive surgery. CONCLUSION: This approval, the first for any regimen for the neoadjuvant treatment of NSCLC in the United States, was supported by a statistically significant and clinically meaningful improvement in EFS with no evidence of detriment in OS or negative impact on patients' receipt and timing of surgery or surgical outcomes.

FDA Approval Summary: Mirvetuximab Soravtansine-Gynx for FRα-Positive, Platinum-Resistant Ovarian Cancer.

On November 14, 2022, the FDA granted accelerated approval to mirvetuximab soravtansine-gynx for treatment of adult patients with folate receptor-α (FRα)-positive, platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal cancer who have received one to three prior systemic therapies. The VENTANA FOLR1 (FOLR-2.1) RxDx Assay was approved as a companion diagnostic device to select patients for this indication. Approval was based on Study 0417 (SORAYA, NCT04296890), a single-arm, multicenter trial. In 104 patients with measurable disease who received mirvetuximab soravtansine-gynx, the overall response rate was 31.7% [95% confidence interval (CI), 22.9-41.6] with a median duration of response of 6.9 months (95% CI, 5.6-9.7). Ocular toxicity was included as a Boxed Warning in the U.S. Prescribing Information (USPI) to alert providers of the risks of developing severe ocular toxicity including vision impairment and corneal disorders. Pneumonitis and peripheral neuropathy were additional important safety risks included as Warnings and Precautions in the USPI. This is the first approval of a targeted therapy for FRα-positive, platinum-resistant ovarian cancer and the first antibody-drug conjugate approved for ovarian cancer. This article summarizes the favorable benefit-risk assessment leading to FDA's approval of mirvetuximab soravtansine-gynx.

US Food and Drug Administration Approval Summary: Fam-Trastuzumab Deruxtecan-nxki for Human Epidermal Growth Factor Receptor 2-Low Unresectable or Metastatic Breast Cancer.

PURPOSE: The US Food and Drug Administration approved fam-trastuzumab deruxtecan-nxki (DS-8201a, T-DXd) for the treatment of adult patients with unresectable or metastatic human epidermal growth factor receptor 2 (HER2)-low (immunohistochemistry 1 + or immunohistochemistry 2+/in situ hybridization-) breast cancer who have received a prior chemotherapy in the metastatic setting or developed disease recurrence during or within 6 months of completing adjuvant chemotherapy. PATIENTS AND METHODS: Approval was based on DESTINY-Breast04, a phase III, randomized, open-label, multicenter trial in patients with unresectable or metastatic HER2-low breast cancer, determined at a central laboratory. A total of 557 patients were randomly assigned (2:1) to receive either T-DXd 5.4 mg/kg intravenously once every 3 weeks (n = 373) or physicians' choice of chemotherapy (n = 184). RESULTS: The study met its primary efficacy end point of progression-free survival (PFS) by blinded independent central review assessment in the hormone receptor-positive (HR+) cohort (N = 494) with an estimated hazard ratio (HR) of 0.51(95% CI, 0.40 to 0.64; P < .0001). Key secondary end points were also met, including PFS in the intent-to-treat population with an HR of 0.50 (95% CI, 0.40 to 0.63; P < .0001), overall survival (OS) in the HR+ cohort with an HR of 0.64 (95% CI, 0.48 to 0.86; P = .0028) and OS in the intent-to-treat with an HR of 0.64 (95% CI, 0.49 to 0.84; P = .0010). The safety profile of T-DXd was consistent with previously approved indications, and no new safety signals were observed in this study population. CONCLUSION: The approval of T-DXd in HER2-low metastatic breast cancer was based on statistically significant and clinically meaningful PFS and OS improvements observed in the DESTINY-Breast04 trial and represents the first approved therapy specifically for the treatment of HER2-low metastatic breast cancer.

Regulatory implications of ctDNA in immuno-oncology for solid tumors.

In the era of precision oncology, use of circulating tumor DNA (ctDNA) is emerging as a minimally invasive approach for the diagnosis and management of patients with cancer and as an enrichment tool in clinical trials. In recent years, the US Food and Drug Administration has approved multiple ctDNA-based companion diagnostic assays for the safe and effective use of targeted therapies and ctDNA-based assays are also being developed for use with immuno-oncology-based therapies. For early-stage solid tumor cancers, ctDNA may be particularly important to detect molecular residual disease (MRD) to support early implementation of adjuvant or escalated therapy to prevent development of metastatic disease. Clinical trials are also increasingly using ctDNA MRD for patient selection and stratification, with an ultimate goal of improving trial efficiency through use of an enriched patient population. Standardization and harmonization of ctDNA assays and methodologies, along with further clinical validation of ctDNA as a prognostic and predictive biomarker, are necessary before ctDNA may be considered as an efficacy-response biomarker to support regulatory decision making.

FDA Approval Summary: Ripretinib for Advanced Gastrointestinal Stromal Tumor.

On May 15, 2020, the FDA approved ripretinib for adult patients with advanced gastrointestinal stromal tumor who have received prior treatment with three or more kinase inhibitors, including imatinib. The approval was based on results from INVICTUS (NCT03353753), an international, multi-center, double-blind, placebo-controlled trial. Patients were randomly allocated (2:1) to receive either ripretinib 150 mg once daily (n = 85) or matching placebo (n = 44). The trial demonstrated a statistically significant improvement in progression-free survival (PFS) as assessed by modified RECIST v1.1 by blinded independent central review for patients randomized to ripretinib, with a median PFS of 6.3 months [95% confidence interval (CI): 4.6-6.9] compared with 1.0 month (95% CI: 0.9-1.7) for placebo [HR: 0.15 (95% CI: 0.09-0.25); P < 0.0001, stratified log-rank test]. There was no statistically significant difference in objective response rate in the ripretinib arm, 9% (95% CI: 4.2-18) compared with placebo 0% [(95% CI: 0-8); P = 0.0504, Fisher exact test]. The median overall survival (OS) in the ripretinib arm was 15.1 months (95% CI: 12.3-15.1) compared with 6.6 months (95% CI: 4.1-11.6) in the placebo arm. A formal statistical comparison of OS was not made due to the prespecified hierarchical analysis plan. The most common (≥20%) adverse events with ripretinib, in order of decreasing frequency, were alopecia, fatigue, nausea, abdominal pain, constipation, myalgia, diarrhea, decreased appetite, palmar-plantar erythrodysesthesia, and vomiting. Other important risks of ripretinib include new primary cutaneous malignancies, hypertension, and cardiac dysfunction.