Scher, Howard I.

TPS389 Background: Recent data have shown that up to 25% of patients with advanced prostate cancer, including mCRPC, have a deleterious germline or somatic mutation in BRCA1, BRCA2, ATM, or another homologous recombination DNA repair gene. Such mutations can be used as a molecular marker to select patients for targeted treatment with poly(ADP-ribose) polymerase inhibitors (PARPis), which are lethal to cells with HRD. Treatment with PARPis has shown preliminary evidence of antitumor activity in patients with mCRPC and a mutation in a homologous recombination DNA repair gene (Mateo et al. N Engl J Med. 2015;373:1697-708). These data provide a compelling rationale for evaluating rucaparib, a potent inhibitor of PARP1, PARP2, and PARP3, in patients with mCRPC associated with HRD. Methods: TRITON3 (NCT02975934) is a randomized, phase 3 study evaluating rucaparib 600 mg BID vs physician’s choice of abiraterone, enzalutamide, or docetaxel in patients with mCRPC and a deleterious germline or somatic BRCA1, BRCA2, or ATM mutation (identified by prior local testing or central testing during screening). Patients must have progressed on androgen receptor signaling–directed therapy in the mCRPC setting; prior PARPi treatment or chemotherapy for mCRPC are exclusion criteria. Patients will be randomly assigned in a 2:1 ratio to either rucaparib or physician’s choice, with the possibility for cross over from the comparator treatment to rucaparib upon radiographic progression confirmed by independent radiology review. The primary endpoint is radiographic progression-free survival (modified RECIST v1.1/PCWG3 criteria) assessed by independent radiology review. Secondary endpoints include objective response rate, duration of response, patient-reported outcomes, overall survival, and safety. Pretreatment blood samples collected from all patients will enable development of a noninvasive plasma-based companion diagnostic to select patients who may benefit from rucaparib treatment. Patients (≈400) will be enrolled at > 100 sites worldwide. Clinical trial information: NCT02975934.

TPS388 Background: Up to 25% of patients with advanced prostate cancer, including mCRPC, have a deleterious germline or somatic mutation in BRCA1, BRCA2, ATM or another homologous recombination (HR) DNA repair gene that can serve as a molecular marker to select those who may respond to poly(ADP-ribose) polymerase inhibitors (PARPis). PARPis are lethal to cells with HRD, and PARPi treatment has shown preliminary evidence of an antitumor effect in patients with mCRPC who harbor a mutation in an HR DNA repair gene (Mateo et al. N Engl J Med. 2015;373:1697-708). These data provide a compelling rationale for evaluating rucaparib, a potent PARP1, PARP2 and PARP3 inhibitor, in patients with mCRPC associated with HRD. Methods: TRITON2 (NCT02952534) is a phase 2 study evaluating rucaparib 600 mg BID in patients with mCRPC. Patients with a deleterious germline or somatic BRCA1, BRCA2 or ATM mutation (per prior local test or central test during screening) will be enrolled into 1 of 2 cohorts based on the presence or absence of measurable visceral and/or nodal disease. An exploratory cohort will enroll patients with an alteration in any of 12 other prespecified HR genes (eg, RAD51C, RAD51D and PALB2), with or without measurable visceral and/or nodal disease. Patients must have progressed on androgen receptor signaling–directed therapy and 1 prior taxane-based chemotherapy for mCRPC. Patients who received prior treatment with a PARPi, mitoxantrone, cyclophosphamide or platinum-based chemotherapy are excluded. The primary endpoint is objective response rate measured using modified RECIST v1.1/PCWG3 for patients with soft-tissue disease and prostate-specific antigen response for patients with nonmeasurable disease. Secondary endpoints include duration of response, radiographic progression-free survival, overall survival, clinical benefit rate and safety. Pretreatment blood samples collected from all patients will enable development of a plasma-based companion diagnostic to select patients who may benefit from rucaparib treatment. Patients (≈160) will be enrolled at > 100 sites worldwide. Clinical trial information: NCT02952534.

LBA2 Background: We previously reported significant benefits in quality of life, patient satisfaction, and emergency room utilization outcomes from a large single-center randomized controlled trial comparing web-based symptom monitoring with patient-reported outcomes (PROs) vs. usual care in patients receiving chemotherapy for metastatic solid tumors (Clinicaltrials.gov: NCT00578006). We now present overall survival results from this trial. Methods: Patients receiving routine outpatient chemotherapy for metastatic solid tumors at Memorial Sloan Kettering Cancer Center were randomly assigned to self-report 12 common symptoms via tablet computers (“PRO intervention”), or to usual care. Treating physicians received symptom printouts at visits and nurses received email alerts when participants reported severe or worsening symptoms. Overall survival was tabulated based on medical records and Social Security Death Index data, estimated using the Kaplan-Meier method, and compared between arms using a log-rank test and Cox proportional hazards regression adjusting for age, sex, race, education level, and cancer type. Results: Between September 2007 and January 2011, 766 patients were randomized, with median age 61 (range 26-91), 86% white, 58% female, and 22% with less than high school education. Cancer types included genitourinary (32% of patients), gynecologic (23%), breast (19%), and lung cancer (26%). Survival results were assessed in June 2016 after a median follow up of 7 years and 517/766 (67%) of participants had died. Median overall survival in the PRO intervention arm was 5 months longer than the control arm (31.2 vs. 26.0 months, p = 0.03). In the multivariable model, results remained statistically significant with a hazard ratio of 0.832 (p = 0.04; 95% CI; 0.696, 0.995). Conclusions: Systematic symptom monitoring during outpatient chemotherapy using web-based patient-reported outcomes confers overall survival benefits. These single-center results are being further evaluated in a national multicenter implementation trial. Clinical trial information: NCT00578006.

52 Background: Ipi enhances antitumor immunity by blocking cytotoxic T-lymphocyte antigen-4. We recently reported the results of CA184-043, a phase 3 study of post-docetaxel mCRPC with Ipi vs Pbo, following single-dose radiotherapy (RT). While the study did not meet the primary endpoint of improving overall survival (HR=0.85, p=0.053), Ipi demonstrated antitumor activity in other efficacy endpoints, including progression-free survival. The present analyses further characterize the safety profile of Ipi in this study. Methods: Safety was evaluated for all treated patients (pts; N=393 for Ipi 10 mg/kg, N=396 for Pbo) starting from first study dose and ending 70 days after the last study dose, including maintenance dosing. Results: Any grade (Gr) irAEs occurred in 63.4% and 21.7% of pts in the Ipi and Pbo arms, respectively. Most common Gr 3/4 irAEs were gastrointestinal (GI) (18.1%; mostly diarrhea and colitis). Gr 3/4 liver irAEs (4.6%) were mostly elevations in AST or ALT. Other Gr 3/4 irAEs were uncommon: endocrine (2.0%), skin (1.0%), and neurological (0.3%). Among Ipi-treated pts, there were no meaningful differences in the frequency or severity of GI AEs between those who received baseline pelvic RT and those who did not (n=141 vs 252; any Gr 77.3% vs 69.8%; Gr 3/4 25.5% vs 21.8%, respectively). There were 5 GI perforations in the Ipi arm (3 within 70 days of last dose [2 related, 1 unrelated], 2 after 70 days of last dose, both related), and none in the Pbo arm. Deaths due to study drug toxicity, as per the investigators, occurred in 4 pts (4, Ipi and 0, Pbo). Conclusions: In this study of Ipi in mCRPC, the most frequent severe irAEs were diarrhea and colitis. Most irAEs were manageable using established treatment algorithms. Clinical trial information: NCT00861614. [Table: see text]

2 Background: The CA184-043 phase 3 study did not reach statistical significance for its primary endpoint of OS (HR=0.85, p=0.053). However, antitumor activity was observed in other efficacy endpoints, including progression-free survival. Prespecified subset analyses were performed to understand if any prognostic features may identify mCRPC patients (pts) more likely to benefit from Ipi treatment. Methods: 799 pts were randomized to receive a single dose of radiotherapy (RT) followed by either Ipi (N=399) or Pbo (N=400). Prespecified subset analyses based on Kaplan-Meier/Cox methodology were performed using known prognostic factors for OS in mCRPC. Results: Prespecified subset analyses suggested that Ipi may be more active in pts with favorable prognostic factors, including no visceral disease, alkaline phosphatase <1.5 ULN, and hemoglobin ≥11 g/dL (Table). The safety profile in this study was consistent with previous reports of Ipi. Conclusions: Based on these subset analyses, Ipi added to RT appears to have greater activity than RT alone in pts with a favorable prognostic profile. These results support continued investigation of Ipi in the ongoing CA184-095 study in chemotherapy-naive mCRPC pts. Clinical trial information: NCT00861614. [Table: see text]

Purpose There is growing interest to enhance symptom monitoring during routine cancer care using patient-reported outcomes, but evidence of impact on clinical outcomes is limited. Methods We randomly assigned patients receiving routine outpatient chemotherapy for advanced solid tumors at Memorial Sloan Kettering Cancer Center to report 12 common symptoms via tablet computers or to receive usual care consisting of symptom monitoring at the discretion of clinicians. Those with home computers received weekly e-mail prompts to report between visits. Treating physicians received symptom printouts at visits, and nurses received e-mail alerts when participants reported severe or worsening symptoms. The primary outcome was change in health-related quality of life (HRQL) at 6 months compared with baseline, measured by the EuroQol EQ-5D Index. Secondary endpoints included emergency room (ER) visits, hospitalizations, and survival. Results Among 766 patients allocated, HRQL improved among more participants in the intervention group than usual care (34% v 18%) and worsened among fewer (38% v 53%; P < .001). Overall, mean HRQL declined by less in the intervention group than usual care (1.4- v 7.1-point drop; P < .001). Patients receiving intervention were less frequently admitted to the ER (34% v 41%; P = .02) or hospitalized (45% v 49%; P = .08) and remained on chemotherapy longer (mean, 8.2 v 6.3 months; P = .002). Although 75% of the intervention group was alive at 1 year, 69% with usual care survived the year (P = .05), with differences also seen in quality-adjusted survival (mean of 8.7 v. 8.0 months; P = .004). Benefits were greater for participants lacking prior computer experience. Most patients receiving intervention (63%) reported severe symptoms during the study. Nurses frequently initiated clinical actions in response to e-mail alerts. Conclusion Clinical benefits were associated with symptom self-reporting during cancer care.