RESUMO
PURPOSE: Recurrent small cell lung cancer (SCLC) has few effective treatments. The EZH2-SLFN11 pathway is a driver of acquired chemoresistance that may be targeted. PATIENTS AND METHODS: This phase I/II trial investigated valemetostat, an EZH1/2 inhibitor, with fixed-dose irinotecan in patients with recurrent SCLC. Phase I primary objectives were to assess safety and a recommended phase II dose (RP2D). The phase II primary objective was to determine overall response rate (ORR), with secondary objectives of duration of response (DoR), progression-free survival (PFS) and overall survival (OS). Immunohistochemistry of pre- and on-treatment tumor biopsies and pharmacokinetics analysis were performed. RESULTS: Twenty-two patients enrolled (phase I, n=12; phase II n=10); one withdrew consent prior to treatment. Three dose-limiting toxicities (DLTs) in dose-escalation resulted in valemetostat 100 mg orally daily selected as RP2D. Among 21 toxicity-evaluable patients, the most frequent (≥20%) treatment-related adverse events were diarrhea, fatigue, nausea, and rash; 3 patients discontinued treatment for toxicity. In phase II, 3/10 patients experienced DLTs triggering a stopping rule. The ORR was 4/19 (21%, 95% CI 6 to 46%). The median DoR, PFS and OS were 4.6 mo, 2.2 mo (95% CI 1.3 to 7.6 mo) and 6.6 mo (95% CI 4.3 to not reached). SLFN11, EZH2 and SCLC subtyping markers did not correlate with response. MHC-I protein expression increased in 4/4 patients with paired biopsies, including 3/3 responders; two responders demonstrated subtype switching on treatment. CONCLUSIONS: Valemetostat and irinotecan was not tolerated but demonstrated efficacy in recurrent SCLC. Valemetostat may warrant further investigation in SCLC.
RESUMO
PURPOSE: Patients with biochemically recurrent prostate cancer (BRPC) after radical prostatectomy and a short PSA doubling time are at risk for distant metastases. Apalutamide, an androgen receptor antagonist, and abiraterone acetate plus prednisone (AAP) prolong survival in the metastatic setting. We evaluated whether intensification of androgen-deprivation therapy (ADT) improves outcomes in BRPC. PATIENTS AND METHODS: PRESTO is a randomized phase III, open-label trial in patients with BRPC and PSA doubling time ≤9 months (ClinicalTrials.gov identifier: NCT03009981). Patients were randomly assigned 1:1:1 to receive a finite 52-week treatment course with ADT control, ADT + apalutamide, or ADT + apalutamide + AAP. The primary end point was PSA progression-free survival (PSA-PFS), defined as serum PSA >0.2 ng/mL after treatment completion. RESULTS: Five hundred three patients were enrolled. The median PSA was 1.8 ng/mL (IQR, 1.0-3.6). At the first planned interim analysis, both experimental arms significantly prolonged PSA-PFS compared with the control arm (median, 24.9 months for ADT + apalutamide v 20.3 months for ADT; hazard ratio [HR], 0.52 [95% CI, 0.35 to 0.77]; P = .00047; median, 26.0 months for ADT + apalutamide + AAP v 20.0 months for ADT; HR, 0.48 [95% CI, 0.32 to 0.71]; P = .00008). Median time to testosterone recovery did not differ across treatment arms. The most common grade ≥3 adverse event was hypertension (7.5%, 7.4%, and 18% in ADT, ADT + apalutamide, and ADT + apalutamide + AAP arms, respectively). CONCLUSION: Intensified AR blockade for a finite duration prolongs PSA-PFS with a manageable safety profile, without adversely affecting time to testosterone recovery. The addition of apalutamide to ADT should be considered in patients with high-risk BRPC.