Rucaparib or Physician's Choice in Metastatic Prostate Cancer.

BACKGROUND: In a phase 2 study, rucaparib, an inhibitor of poly(ADP-ribose) polymerase (PARP), showed a high level of activity in patients who had metastatic, castration-resistant prostate cancer associated with a deleterious BRCA alteration. Data are needed to confirm and expand on the findings of the phase 2 study. METHODS: In this randomized, controlled, phase 3 trial, we enrolled patients who had metastatic, castration-resistant prostate cancer with a BRCA1, BRCA2, or ATM alteration and who had disease progression after treatment with a second-generation androgen-receptor pathway inhibitor (ARPI). We randomly assigned the patients in a 2:1 ratio to receive oral rucaparib (600 mg twice daily) or a physician's choice control (docetaxel or a second-generation ARPI [abiraterone acetate or enzalutamide]). The primary outcome was the median duration of imaging-based progression-free survival according to independent review. RESULTS: Of the 4855 patients who had undergone prescreening or screening, 270 were assigned to receive rucaparib and 135 to receive a control medication (intention-to-treat population); in the two groups, 201 patients and 101 patients, respectively, had a BRCA alteration. At 62 months, the duration of imaging-based progression-free survival was significantly longer in the rucaparib group than in the control group, both in the BRCA subgroup (median, 11.2 months and 6.4 months, respectively; hazard ratio, 0.50; 95% confidence interval [CI], 0.36 to 0.69) and in the intention-to-treat group (median, 10.2 months and 6.4 months, respectively; hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001 for both comparisons). In an exploratory analysis in the ATM subgroup, the median duration of imaging-based progression-free survival was 8.1 months in the rucaparib group and 6.8 months in the control group (hazard ratio, 0.95; 95% CI, 0.59 to 1.52). The most frequent adverse events with rucaparib were fatigue and nausea. CONCLUSIONS: The duration of imaging-based progression-free survival was significantly longer with rucaparib than with a control medication among patients who had metastatic, castration-resistant prostate cancer with a BRCA alteration. (Funded by Clovis Oncology; TRITON3 ClinicalTrials.gov number, NCT02975934.).

Avelumab as neoadjuvant therapy in patients with urothelial non-metastatic muscle invasive bladder cancer: a multicenter, randomized, non-comparative, phase II study (Oncodistinct 004 - AURA trial).

INTRODUCTION: Cisplatin-based neoadjuvant chemotherapy (NAC) followed by surgery is the standard treatment for patients with non-metastatic muscle invasive bladder cancer (MIBC). Unfortunately, many patients are not candidates to receive cisplatin due to renal impairment. Additionally, no predictive biomarkers for pathological complete response (pCR) are currently validated in clinical practice. Studies evaluating immune checkpoint inhibitors in the peri-operative setting are emerging with promising results. Clinical trials are clearly required in the neoadjuvant setting in order to improve therapeutic strategies. METHODS AND ANALYSIS: Oncodistinct 004 - AURA is an ongoing multicenter phase II randomized trial assessing the efficacy and safety of avelumab single-agent or combined to different NAC regimens in patients with non-metastatic MIBC. Patients are enrolled in two distinct cohorts according to their eligibility to receive cisplatin-based NAC. In the cisplatin eligible cohort, patients are randomized in a 1:1 fashion to receive avelumab combined with cisplatin-gemcitabine or with dose-dense methotrexate-vinblastine-doxorubicin-cisplatin. In the cisplatin ineligible cohort, patients are randomized at a 1:1 ratio to paclitaxel-gemcitabine associated to avelumab or avelumab alone. Primary endpoint is pCR. Secondary endpoints are pathological response and safety. ETHICS AND DISSEMINATION: The study is approved by ethics committee from all participating centers. All participants provide informed consent prior inclusion to the study. Once completed, results will be published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov (NCT03674424).

Randomized Phase II Study of Cabazitaxel Versus Methotrexate in Patients With Recurrent and/or Metastatic Squamous Cell Carcinoma of the Head and Neck Previously Treated With Platinum-Based Therapy.

LESSONS LEARNED: Cabazitaxel has activity in squamous cell carcinoma of the head and neck (SCCHN) and taxane-resistant cell lines. For the first time, cabazitaxel was investigated in incurable patients with recurrent SCCHN. Patients were randomly assigned to cabazitaxel every 3 weeks or weekly methotrexate.This phase II study did not meet its primary endpoint.Cabazitaxel has low activity in SCCHN.The toxicity profile in this population also was not favorable owing to the high rate of febrile neutropenia observed (17%). BACKGROUND: Cabazitaxel is a second-generation taxane that improves the survival of patients with metastatic castrate-resistant prostate cancer following docetaxel therapy. Cabazitaxel has activity in squamous cell carcinoma of the head and neck (SCCHN) and taxane-resistant cell lines. In this randomized phase II trial, we investigated cabazitaxel in patients with recurrent SCCHN. METHODS: Patients with incurable SCCHN with progression after platinum-based therapy were randomly assigned to cabazitaxel every 3 weeks (cycle 1, 20 mg/m2, increased to 25 mg/m2 for subsequent cycles in the absence of nonhematological adverse events [AEs] greater than grade 2 and hematological AEs greater than grade 3) or methotrexate (40 mg/m2/week). The patients were stratified according to their performance status and previous platinum-based chemotherapy for palliation versus curative intent. The primary endpoint was the progression-free survival rate (PFSR) at 18 weeks. RESULTS: Of the 101 patients, 53 and 48, with a median age of 58.0 years (range, 41-80), were randomly assigned to cabazitaxel or methotrexate, respectively. The PFSR at 18 weeks was 13.2% (95% confidence interval [CI], 5%-25%) for cabazitaxel and 8.3% (95% CI, 2%-20%) for methotrexate. The median progression-free survival was 1.9 months in both arms. The median overall survival was 5.0 and 3.6 months for cabazitaxel and methotrexate, respectively. More patients experienced serious adverse events with cabazitaxel than with methotrexate (54% vs. 36%). The most common drug-related grade 3-4 AE in the cabazitaxel arm was febrile neutropenia (17.3%). CONCLUSION: This study did not meet its primary endpoint. Cabazitaxel has low activity in recurrent SCCHN.

Phase II study of dual phosphoinositol-3-kinase (PI3K) and mammalian target of rapamycin (mTOR) inhibitor BEZ235 in patients with locally advanced or metastatic transitional cell carcinoma.

OBJECTIVE: To assess, in a multicentre phase II trial, the safety and efficacy of BEZ235, an oral pan-class I phosphoinositol-3-kinase (PI3K) and mammalian target of rapamycin (mTOR) complex1/2 inhibitor, in locally advanced or metastatic transitional cell carcinoma (TCC) after failure of platinum-based therapy. PATIENTS AND METHODS: Patients with locally advanced or metastatic TCC progressing after platinum therapy were prospectively stratified by PI3K/Akt/mTOR pathway alterations, defined as PTEN loss and PIK3CA mutation. All patients received BEZ235 until progressive disease or unacceptable toxicity. The primary endpoint was the progression-free survival (PFS) rate at 16 weeks. This study was, however, closed prematurely because BEZ235 was withdrawn from further development. RESULTS: A total of 20 patients (18 without and two with PI3K/Akt/mTOR alterations) were enrolled and received BEZ235. One partial response (5%) and two cases of stable disease (10%) were observed, all in patients without PI3K/mTOR pathway alterations. The PFS rate at 8 and 16 weeks was 15 and 10%, respectively; the median (range) PFS was 62 (38-588) days (95% confidence interval [CI] 53-110); and the median (range) overall survival was 127 (41-734) days (95% CI 58-309). Among the 90% of patients who experienced drug-related adverse events of any grade, 50% experienced grade 3-4 adverse events, including stomatitis (15%), fatigue (5%), nausea (5%), diarrhoea (5%), renal failure (5%), cutaneous rash (5%), hepatotoxicity (5%) and hypertension (5%). CONCLUSION: BEZ235 showed modest clinical activity and an unfavourable toxicity profile in patients with advanced and pretreated TCC; however, a minority of patients experienced a clinical benefit, suggesting that a complete blockade of the PI3K/mTOR axis could improve outcome in some specific patients. Furthermore, this study showed that molecular stratification of patients for personalized medicine before treatment is feasible.

Weekly cisplatin with radiotherapy for locally advanced head and neck squamous cell carcinoma.

PURPOSE: Although commonly used for the treatment of locally advanced head and neck squamous cell carcinoma (HNSCC) concomitant radio-chemotherapy (RT-CT) with weekly cisplatin has not been definitely studied. We conducted a single centre retrospective study with the aim to evaluate efficacy and acute toxicity of definitive concomitant RT-CT with 40 mg/m2 weekly cisplatin in patients with locally advanced HNSCC with a particular emphasis on RT modality (conventional or accelerated) and dose of cisplatin delivered. METHODS: One hundred and twelve consecutive patients were included. They were given cisplatin 40 mg/m2)week concomitantly with conventionally fractionated (CFRT) (N=33) or accelerated (ART) (N=79) RT. RESULTS: RT was delivered according to the treatment plan in 104 patients and full dose was given to 107 patients. A median cumulative cisplatin dose of 240 mg/m2 was administered to patients treated with CFRT and of 200 mg/m2 to those treated with ART. Overall complete response rate was 81.3%. With a median follow up of 38.4 months, median overall survival (OS) was 75 months, not influenced by RT type or cisplatin dose received. The most clinically significant grade 3 or 4 acute toxicities were stomatitis (35.7%), neutropenia (25%), anemia (12.5%) and acute kidney injury (5.4%). CONCLUSIONS: Our study shows that a median cumulative dose of 200 mg/m2 cisplatin can be safely administered using a weekly regimen to patients treated with concomitant RT (CFRT or ART). Efficacy results and toxicity compare favorably with those described with triweekly cisplatin RT-CT, suggesting that a randomized comparison should be undertaken.

Characterization of exclusive rib lesions detected by [68Ga]Ga-PSMA-11 PET/CT.

OBJECTIVE: The objective of this study was to characterize exclusive costal lesions detected by 68Gallium-labelled prostate-specific membrane antigen ([68Ga]Ga-PSMA-11) PET/computed tomography (CT) at initial staging or biochemical recurrence (BCR) in prostate cancer (PCa) patients, and to identify clinical and/or PET/CT criteria associated with benign and malignant lesions. METHODS: We retrospectively identified 54 patients with PCa who underwent [68Ga]Ga-PSMA-11 PET/CT for initial staging (N = 39) or BCR (N = 15) and whose reports described rib lesions, at the exclusion of any other lesions, whether doubtful, suspicious, or established. Posttherapy prostate-specific antigen (PSA) levels were used to determine whether those lesions were benign or malignant. Each patient's prostate-specific membrane antigen PET/CT report was classified as true positive, true negative, false positive, or false negative based on the posttherapy PSA level. We then assessed whether any clinical and/or PET/CT criteria could help differentiate benign from malignant lesions, and if any criteria were misleading. RESULTS: Among the 54 patients, 46 (85.2%) had 64 benign costal lesions, and eight (14.8%) had 10 malignant lesions. PET/CT reports indicated rib lesions as benign/equivocal in 38/54 (55.6%) patients and malignant in 16/54 (29.6%). Benign features on CT were the only parameter significantly associated with the final diagnosis. Factors such as patient age, maximum standardized uptake value of lesions, lesion dispersion, and malignant features described on CT were found to be misleading when deciding the malignant or benign status. CONCLUSION: Most exclusive costal lesions detected by [68Ga]Ga-PSMA-11 PET/CT are benign. Apart from specific benign CT features, no clinical or PET/CT criteria reliably differentiate benign from malignant costal lesions.

Androgen receptor pathway inhibitors and taxanes in metastatic prostate cancer: an outcome-adaptive randomized platform trial.

ProBio is the first outcome-adaptive platform trial in prostate cancer utilizing a Bayesian framework to evaluate efficacy within predefined biomarker signatures across systemic treatments. Prospective circulating tumor DNA and germline DNA analysis was performed in patients with metastatic castration-resistant prostate cancer before randomization to androgen receptor pathway inhibitors (ARPIs), taxanes or a physician's choice control arm. The primary endpoint was the time to no longer clinically benefitting (NLCB). Secondary endpoints included overall survival and (serious) adverse events. Upon reaching the time to NLCB, patients could be re-randomized. The primary endpoint was met after 218 randomizations. ARPIs demonstrated ~50% longer time to NLCB compared to taxanes (median, 11.1 versus 6.9 months) and the physician's choice arm (median, 11.1 versus 7.4 months) in the biomarker-unselected or 'all' patient population. ARPIs demonstrated longer overall survival (median, 38.7 versus 21.7 and 21.8 months for taxanes and physician's choice, respectively). Biomarker signature findings suggest that the largest increase in time to NLCB was observed in AR (single-nucleotide variant/genomic structural rearrangement)-negative and TP53 wild-type patients and TMPRSS2-ERG fusion-positive patients, whereas no difference between ARPIs and taxanes was observed in TP53-altered patients. In summary, ARPIs outperform taxanes and physician's choice treatment in patients with metastatic castration-resistant prostate cancer with detectable circulating tumor DNA. ClinicalTrials.gov registration: NCT03903835 .

Emergence of BRCA Reversion Mutations in Patients with Metastatic Castration-resistant Prostate Cancer After Treatment with Rucaparib.

BACKGROUND: Poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors are approved in the USA for the treatment of patients with BRCA1 or BRCA2 (BRCA) mutated (BRCA+) metastatic castration-resistant prostate cancer (mCRPC). BRCA reversion mutations are a known mechanism of acquired resistance to PARP inhibitors in multiple cancer types, although their impact and prevalence in mCRPC remain unknown. OBJECTIVE: To examine the prevalence of BRCA reversion mutations in the plasma of patients with BRCA+ mCRPC after progression on rucaparib. DESIGN, SETTING, AND PARTICIPANTS: Men with BRCA+ mCRPC enrolled in Trial of Rucaparib in Prostate Indications 2 (TRITON2) were treated with rucaparib after progressing on one to two lines of androgen receptor-directed and one taxane-based therapy. Cell-free DNA from the plasma of 100 patients, collected at the end of treatment after confirmed progression before May 5, 2020, was queried for BRCA reversion mutations using next-generation sequencing (NGS). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The association of clinical efficacy and postprogression genomics was measured in 100 patients with BRCA+ mCRPC treated with rucaparib. RESULTS AND LIMITATIONS: No baseline BRCA reversion mutations were observed in 100 BRCA+ patients. NGS identified somatic BRCA reversion mutations in 39% (39/100) of patients after progression. Reversion rates were similar for BRCA2 and BRCA1, irrespective of germline or somatic status, but higher in samples with a high tumor DNA fraction. Most patients with reversions (74%, 29/39) had two or more reversion mutations occurring subclonally at lower allele frequencies than the original BRCA mutations. The incidence of BRCA reversion mutations increased with the duration of rucaparib treatment. The frequency of reversion mutations was higher in patients with an objective (58%) or a prostate-specific antigen (69%) response compared with those without either (39% and 29%, respectively). CONCLUSIONS: These findings suggest that BRCA reversion mutations are a significant mechanism of acquired resistance to rucaparib in patients with BRCA+ mCRPC, with evidence of subclonal convergence promoting systemic resistance. PATIENT SUMMARY: Men with BRCA mutated metastatic castration-resistant prostate cancer enrolled in TRITON2 were treated with rucaparib after progressing on one to two lines of androgen receptor-directed and one taxane-based therapy. Cell-free DNA from the plasma of 100 patients, collected after radiographic or prostate-specific antigen progression before May 5, 2020, was analyzed by next-generation sequencing and queried for BRCA reversion mutations.

Rucaparib for the Treatment of Metastatic Castration-resistant Prostate Cancer Associated with a DNA Damage Repair Gene Alteration: Final Results from the Phase 2 TRITON2 Study.

BACKGROUND: Initial TRITON2 (NCT02952534) results demonstrated the efficacy of rucaparib 600 mg BID in patients with metastatic castration-resistant prostate cancer (mCRPC) associated with a BRCA1 or BRCA2 (BRCA) or other DNA damage repair (DDR) gene alteration. OBJECTIVE: To present the final data from TRITON2. DESIGN, SETTING, AND PARTICIPANTS: TRITON2 enrolled patients with mCRPC who had progressed on one or two lines of next-generation androgen receptor-directed therapy and one taxane-based chemotherapy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was objective response rate (ORR; as per the modified Response Evaluation Criteria in Solid Tumor Version 1.1/Prostate Cancer Clinical Trials Working Group 3 criteria in patients with measurable disease by independent radiology review [IRR]); prostate-specific antigen (PSA) response rate (≥50% decrease from baseline [PSA50]) was a key secondary endpoint. RESULTS AND LIMITATIONS: As of July 27, 2021 (study closure), TRITON2 had enrolled 277 patients, grouped by mutated gene: BRCA (n = 172), ATM (n = 59), CDK12 (n = 15), CHEK2 (n = 7), PALB2 (n = 11), or other DDR gene (Other; n = 13). ORR by IRR was 46% (37/81) in the BRCA subgroup (95% confidence interval [CI], 35-57%), 100% (4/4) in the PALB2 subgroup (95% CI, 40-100%), and 25% (3/12) in the Other subgroup (95% CI, 5.5-57%). No patients within the ATM, CDK12, or CHEK2 subgroups had an objective response by IRR. PSA50 response rates (95% CI) in the BRCA, PALB2, ATM, CDK12, CHEK2, and Other subgroups were 53% (46-61%), 55% (23-83%), 3.4% (0.4-12), 6.7% (0.2-32%), 14% (0.4-58%), and 23% (5.0-54%), respectively. CONCLUSIONS: The final TRITON2 results confirm the clinical benefit and manageable safety profile of rucaparib in patients with mCRPC, including those with an alteration in BRCA or select non-BRCA DDR gene. PATIENT SUMMARY: Almost half of TRITON2 patients with BRCA-mutated metastatic castration-resistant prostate cancer had a complete or partial tumor size reduction with rucaparib; clinical benefits were also observed with other DNA damage repair gene alterations.

A Case Study of Clinical Response to Rucaparib in a Patient with Metastatic Castration-Resistant Prostate Cancer and a RAD51B Alteration.

PARP inhibitors, such as rucaparib, have been well characterized in metastatic castration-resistant prostate cancer (mCRPC) associated with BRCA alterations, and the clinical activity of these agents has also been evaluated in patients with mCRPC associated with alterations in other non-BRCA DNA damage repair (DDR) genes, including RAD51B. There is likely a differential sensitivity to PARP inhibition based on the specific DDR gene altered, but research in this area is limited because of the low frequency of alterations in these genes. Here, we describe a mCRPC patient with a truncating rearrangement of RAD51B who had a radiographic and PSA response when treated with the PARP inhibitor rucaparib within the TRITON2 trial. We investigated the patients' response parameters, circulating tumor DNA (ctDNA) fraction and tumor genomics longitudinally, using next-generation sequencing (NGS) of tissue and plasma. ctDNA fraction correlates with radiographic and PSA response and is lower during times of response. NGS did not reveal any potential genomic mechanism of acquired drug resistance. This case shows evidence for rucaparib activity in a rare patient with mCRPC and a RAD51B truncation.

Using 68Ga-PSMA-11 PET/CT for Therapy Response Assessment in Patients with Metastatic Castration-Resistant Prostate Cancer: Application of EAU/EANM Recommendations in Clinical Practice.

For patients with metastatic castration-resistant prostate cancer (mCRPC), no reliable biomarkers for predicting therapeutic response or assisting in treatment selection and sequencing are currently available. Using the recent European Association of Urology and European Association of Nuclear Medicine recommendations, we aimed to compare response assessment between prostate-specific membrane antigen (PSMA) PET/CT and conventional imaging in mCRPC patients starting first-line treatment with a novel hormonal agent (NHA) and to perform a sequential comparative analysis of PSMA PET/CT-derived parameters after 4 and 12 wk of therapy. Methods: Data from 18 mCRPC patients who started NHA treatment and underwent 68Ga-PSMA-11 PET/CT before therapy initiation (baseline), at week 4 (W4), and at week 12 (W12) in addition to conventional imaging (bone scintigraphy, CT) at baseline and W12 were retrospectively included. PET/CT images were quantitatively analyzed for maximum and mean SUV and total PSMA ligand-positive lesions. Comparative analysis of PET/CT-derived parameters was performed, and patients were classified as having nonprogressive disease or progressive disease (PD) according to 68Ga-PSMA-11 PET/CT, prostate-specific antigen, and conventional imaging criteria. Results: Treatment response was evaluable by 68Ga-PSMA-11 PET/CT in 16 of 18 patients (89%) and by conventional imaging in 11 of 18 patients (61%). Five of 16 patients classified as having PD by 68Ga-PSMA-11 PET/CT at W12 had already met progression criteria at W4, and substantial agreement was observed between W4 and W12 (κ, 0.74) 68Ga-PSMA-11 PET/CT results. Nonetheless, 2 of 16 patients (13%) were incorrectly classified as having PD because of a flare phenomenon on PSMA PET/CT that disappeared at W12. Conclusion: Volumetric assessments of 68Ga-PSMA-11 PET/CT imaging can improve response evaluation in NHA-treated patients with mCRPC. Although early response assessments at W4 need to be approached with caution because of flare, 68Ga-PSMA-11 PET/CT imaging at W4 and W12 revealed substantial agreement in therapy response assessments; these findings warrant further investigation to distinguish PD from flare at W4 and help improve the understanding of resistance to therapy.

Oncological patients' reactions to COVID-19 pandemic: A single institution prospective study.

BACKGROUND: The spread of the COVID-19 pandemic has led to a rapid reorganization in all human and hospital activities, with impact on cancer patients. AIM: An analysis of cancer patients fears, and awareness of COVID-19 has been done in this study. METHODS AND RESULTS: We analyzed cancer patients' reactions to the pandemic and their perception of oncological care reorganization, through a 12-item survey, proposed at the peak of pandemic and 3 months later. Overall, 237 patients were included in the study. During the peak of pandemic 34.6% of patients were more worried about COVID-19 than cancer versus 26.4% in the post-acute phase (p = .013). Although 49.8% of patients in the acute phase and 42.3% in the post-acute phase considered their risk of death if infected ≥50%, and more than 70% of patients thought to be at higher risk of complications, the majority of them did not consider the possibility to stop or delay their treatment. Patients were more interested in following news about COVID-19 than cancer and they complied with all preventive measures in more than 90% of the cases. CONCLUSIONS: Although cancer patients worried about COVID-19 and evaluated the risk of complication or death due to COVID-19 as extremely high, they were still asking for the best oncological treatment.

Cemiplimab for Cisplatin Resistant Metastatic Penile Cancer.

We report on a 75-year old man who presented with metastatic, squamous-cell carcinoma (SCC) of the penis whose disease had progressed after radiotherapy (RT) and cisplatin-based chemotherapy (CT). A strong PD-L1 expression as well as a CDKN2A mutation was documented, and he was given cemiplimab every 3 weeks at time of disease progression. Complete response (CR) was demonstrated after 10 cycles, and no toxicity was reported. However, this treatment was stopped after 13 cycles when the patient developed moderate severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pneumonitis which required a 2-week hospitalization for oxygen support. Six months later, he remains in CR. To our knowledge, this is the first demonstration of a CR with cemiplimab in a metastatic penile SCC patient previously treated with CT and RT for relapse. Furthermore, the patient remains disease-free despite cemiplimab was withdrawn due to SARS-CoV-2 pneumonitis.

Response to Rucaparib in BRCA-Mutant Metastatic Castration-Resistant Prostate Cancer Identified by Genomic Testing in the TRITON2 Study.

PURPOSE: The PARP inhibitor rucaparib is approved in the United States for patients with metastatic castration-resistant prostate cancer (mCRPC) and a deleterious germline and/or somatic BRCA1 or BRCA2 (BRCA) alteration. While sequencing of tumor tissue is considered the standard for identifying patients with BRCA alterations (BRCA+), plasma profiling may provide a minimally invasive option to select patients for rucaparib treatment. Here, we report clinical efficacy in patients with BRCA+ mCRPC identified through central plasma, central tissue, or local genomic testing and enrolled in TRITON2. PATIENTS AND METHODS: Patients had progressed after next-generation androgen receptor-directed and taxane-based therapies for mCRPC and had BRCA alterations identified by central sequencing of plasma and/or tissue samples or local genomic testing. Concordance of plasma/tissue BRCA status and objective response rate and prostate-specific antigen (PSA) response rates were summarized. RESULTS: TRITON2 enrolled 115 patients with BRCA+ identified by central plasma (n = 34), central tissue (n = 37), or local (n = 44) testing. Plasma/tissue concordance was determined in 38 patients with paired samples and was 47% in 19 patients with a somatic BRCA alteration. No statistically significant differences were observed between objective and PSA response rates to rucaparib across the 3 assay groups. Patients unable to provide tissue samples and tested solely by plasma assay responded at rates no different from patients identified as BRCA+ by tissue testing. CONCLUSIONS: Plasma, tissue, and local testing of mCRPC patients can be used to identify men with BRCA+ mCRPC who can benefit from treatment with the PARP inhibitor rucaparib.

Rucaparib in Men With Metastatic Castration-Resistant Prostate Cancer Harboring a BRCA1 or BRCA2 Gene Alteration.

PURPOSE: BRCA1 or BRCA2 (BRCA) alterations are common in men with metastatic castration-resistant prostate cancer (mCRPC) and may confer sensitivity to poly(ADP-ribose) polymerase inhibitors. We present results from patients with mCRPC associated with a BRCA alteration treated with rucaparib 600 mg twice daily in the phase II TRITON2 study. METHODS: We enrolled patients who progressed after one to two lines of next-generation androgen receptor-directed therapy and one taxane-based chemotherapy for mCRPC. Efficacy and safety populations included patients with a deleterious BRCA alteration who received ≥ 1 dose of rucaparib. Key efficacy end points were objective response rate (ORR; per RECIST/Prostate Cancer Clinical Trials Working Group 3 in patients with measurable disease as assessed by blinded, independent radiology review and by investigators) and locally assessed prostate-specific antigen (PSA) response (≥ 50% decrease from baseline) rate. RESULTS: Efficacy and safety populations included 115 patients with a BRCA alteration with or without measurable disease. Confirmed ORRs per independent radiology review and investigator assessment were 43.5% (95% CI, 31.0% to 56.7%; 27 of 62 patients) and 50.8% (95% CI, 38.1% to 63.4%; 33 of 65 patients), respectively. The confirmed PSA response rate was 54.8% (95% CI, 45.2% to 64.1%; 63 of 115 patients). ORRs were similar for patients with a germline or somatic BRCA alteration and for patients with a BRCA1 or BRCA2 alteration, while a higher PSA response rate was observed in patients with a BRCA2 alteration. The most frequent grade ≥ 3 treatment-emergent adverse event was anemia (25.2%; 29 of 115 patients). CONCLUSION: Rucaparib has antitumor activity in patients with mCRPC and a deleterious BRCA alteration, but with a manageable safety profile consistent with that reported in other solid tumor types.

Non-BRCA DNA Damage Repair Gene Alterations and Response to the PARP Inhibitor Rucaparib in Metastatic Castration-Resistant Prostate Cancer: Analysis From the Phase II TRITON2 Study.

PURPOSE: Genomic alterations in DNA damage repair (DDR) genes other than BRCA may confer synthetic lethality with PARP inhibition in metastatic castration-resistant prostate cancer (mCRPC). To test this hypothesis, the phase II TRITON2 study of rucaparib included patients with mCRPC and deleterious non-BRCA DDR gene alterations. PATIENTS AND METHODS: TRITON2 enrolled patients who had progressed on one or two lines of next-generation androgen receptor-directed therapy and one taxane-based chemotherapy for mCRPC. Key endpoints were investigator-assessed radiographic response per modified RECIST/PCWG3 and PSA response (≥50% decrease from baseline). RESULTS: TRITON2 enrolled 78 patients with a non-BRCA DDR gene alteration [ATM (n = 49), CDK12 (n = 15), CHEK2 (n = 12), and other DDR genes (n = 14)]. Among patients evaluable for each endpoint, radiographic and PSA responses were observed in a limited number of patients with an alteration in ATM [2/19 (10.5%) and 2/49 (4.1%), respectively], CDK12 [0/10 (0%) and 1/15 (6.7%), respectively], or CHEK2 [1/9 (11.1%) and 2/12 (16.7%), respectively], including no radiographic or PSA responses in 11 patients with confirmed biallelic ATM loss or 11 patients with ATM germline mutations. Responses were observed in patients with alterations in the DDR genes PALB2, FANCA, BRIP1, and RAD51B. CONCLUSIONS: In this prospective, genomics-driven study of rucaparib in mCRPC, we found limited radiographic/PSA responses to PARP inhibition in men with alterations in ATM, CDK12, or CHEK2. However, patients with alterations in other DDR-associated genes (e.g., PALB2) may benefit from PARP inhibition.See related commentary by Sokolova et al., p. 2439.

Randomised phase II study of second-line olaratumab with mitoxantrone/prednisone versus mitoxantrone/prednisone alone in metastatic castration-resistant prostate cancer.

INTRODUCTION: Platelet-derived growth factor receptor-α (PDGFRα) is expressed in primary prostate adenocarcinoma and in associated skeletal metastases. Olaratumab is a fully human monoclonal antibody that binds PDGFRα and blocks downstream signalling. This phase II study assessed the efficacy and safety of olaratumab in combination with mitoxantrone and prednisone (M/P) versus M/P alone in patients with metastatic castration-resistant prostate cancer (mCRPC) who progressed after docetaxel. METHODS: Patients were randomised to receive 21-d cycles of olaratumab (15 mg/kg, Days 1 and 8) plus mitoxantrone (12 mg/m2, Day 1) and prednisone (5 mg, twice daily) or M/P alone. Progression-free survival (PFS) was the primary end-point. Secondary end-points included overall survival (OS), safety, and circulating tumour cell (CTC) counts. RESULTS: A total of 123 patients were randomised, 63 to olaratumab + M/P and 60 to M/P. Median PFS was 2.3 months for olaratumab + M/P and 2.4 months for M/P (hazard ratio [HR] = 1.29; 95% confidence interval [CI] = 0.87-1.90). Median OS was 14.2 months for olaratumab + M/P and 12.8 months for M/P (HR = 1.08; 95% CI = 0.72-1.61). Both treatment arms had similar toxicity profiles; neutropenia (24% versus 15%), anaemia (13% versus 14%) and fatigue (11% versus 9%) (olaratumab + M/P versus M/P, respectively) were the most common grade ≥3 events. High CTC count was associated with poorer OS in both arms. Patients with very high cell counts (>37 cells/7.5 ml) exhibited improved OS with olaratumab + M/P (interaction P = 0.043). CONCLUSIONS: Olaratumab + M/P had an acceptable safety profile but did not improve the efficacy of M/P chemotherapy. Further study with selected patient populations and earlier in the disease course might be considered.

Optimization of recombinant human erythropoietin therapy after allogeneic hematopoietic stem cell transplantation.

OBJECTIVE: Allogeneic hematopoietic stem cell transplantation (HSCT) is associated with prolonged anemia caused by defective erythropoietin (Epo) production. We enrolled 34 recipients of an allogeneic HSCT in three consecutive trials to determine the optimal utilization of recombinant human erythropoietin (rhEpo) therapy in this setting. MATERIALS AND METHODS: In the first trial (n = 7), rhEpo 1400 U/kg/week was given from day 1 until a hemoglobin (Hb) level of 10 g/dL was achieved, for a maximum of 60 days. In the second trial, rhEpo 500 U/kg/week was given to achieve Hb levels of 13 to 14 g/dL in 13 anemic patients with fatigue 56 to 1440 days after transplant. In the third trial, rhEpo was scheduled to start on day 35 in 14 patients at a dose of 500 U/kg/week with the aim of achieving Hb levels of 13 to 14 g/dL. RESULTS: In trial 1, erythroid recovery to 1% reticulocytes and red blood cell transfusion independence were faster, but the number of transfusions was not reduced compared to 10 controls. Responses were brisk in trial 2, with transfusion independence achieved after a median of 1 week in 12 of 13 patients, and 2-g Hb increments or Hb values of 11, 12, and 13 g/dL after 6, 7, 10, and 10 weeks, respectively. Transfusions were significantly reduced in the first month of rhEpo therapy. In trial 3, transfusion independence was obtained after a median of 1 week in 13 of 14 patients, and 2-g Hb increments or Hb values of 11, 12, and 13 g/dL after 3, 4, 6, and 8 weeks, respectively. Transfusions rates were considerably reduced compared to the previous month in the same patients or compared to controls undergoing peripheral blood or marrow transplant without rhEpo. CONCLUSIONS: Anemia after allogeneic HSCT is exquisitely sensitive to rhEpo. The benefit is minimal when it is given early post-transplant, as used in all trials to date. However, the rate of major response is greater than 90% when rhEpo is started after day 35. These data provide the basis on which to conduct a prospective, randomized, placebo-controlled trial of rhEpo therapy after allogeneic HSCT.