Assessing olaparib efficacy in U.S. Veterans with metastatic prostate cancer utilizing a time-indifferent g-rate method ideal for real-world analyses.

BACKGROUND: We aimed to assess real-world efficacy of the PARP inhibitor, olaparib, in US Veterans with metastatic prostate cancer (mPC) by leveraging the national data repository and evaluate a novel approach to assess treatment efficacy in tumors considered rare or harboring rare mutations. METHODS: Included Veterans had 1) mPC with somatic or germline alterations/mutations in genes involved in homologous recombination repair (HRR), 2) received olaparib monotherapy as well as a novel hormonal therapy/androgen receptor pathway inhibitors (NHT/ARPI), and/or chemotherapy, and 3) estimable rates of tumor growth (g-rate) using PSA values obtained while receiving treatment. Previous work has shown an excellent inverse correlation of g-rate with survival. Using g-rate, we determined tumor doubling time (DT) and DT ratios (DT on olaparib/DT on prior medication). We postulated that a DT ratio≥ 1 was associated with benefit. FINDINGS: We identified 139 Veterans, including 42 Black males with tumors harboring mutations/alterations in HRR genes who received olaparib: BRCA2 (50), ATM (32), BRCA1 (10), other mutations (47). 62/139 (45%) of all and 21/42 (50%) of Black Veterans had DT ratios ≥1, including 31, 10, 2, and 19 with BRCA2, ATM, BRCA1, and other mutations, respectively (p = 0.006). Median survival with DT ratios ≥1 was superior, being 24.5 vs. 11.4 months for DT ratio <1 (p = 0.01, HR 0.50, 95% CI 0.29-0.85). Benefit from olaparib, defined as DT ratio ≥1, was not observed for germline status, starting PSA value, number of prior therapies, or immediate prior therapy. Compared to matched cohorts, tumors in the olaparib cohort had shorter DTs with enzalutamide in first line (367 vs. 884 days; p = 0.0043). INTERPRETATION: Using equations indifferent to timing of assessments ideal for real-world efficacy analyses, we showed DT ratio ≥1 representing slower tumor growth on olaparib relative to the prior therapy correlates with improved survival. Olaparib efficacy in Veterans with mPC harboring mutations/alterations in HRR genes emulates clinical trial results. Black men had comparable results. Compared to matched cohorts, in first line, enzalutamide was less efficacious in tumors harboring mutations/alterations in HRR genes. FUNDING: American Society of Clinical Oncology Conquer Cancer Foundation (ASCO CCF), the Blavatnik Family Foundation and the Prostate Cancer Foundation (PCF).

Assessment of PSA responses and changes in the rate of tumor growth (g-rate) with immune checkpoint inhibitors in US Veterans with prostate cancer.

We examined data from US Veterans with prostate cancer (PC) to assess disease response to immune checkpoint inhibitors (ICI) as monotherapy or combined with abiraterone or enzalutamide to assess ICI efficacy in the real-world. We queried the VA corporate data warehouse (CDW) to identify Veterans with a diagnosis of PC who received ICI for any malignancy and had ≥1 PSA measurement while receiving ICI. To evaluate ICI monotherapy, we restricted analysis to Veterans who had not received LHRH agonists/antagonists, PC-directed medical therapy, or radiation/extirpative surgery of the bladder/prostate within and preceding the duration of ICI administration. For ICI combination analysis, we identified Veterans who received abiraterone or enzalutamide for PC while on ICI. We calculated rates of tumor (PSA) growth (g-rates), comparing them to a 1:2 matched reference cohort. We identified 787 Veterans with PC and ≥1 PSA measurement while receiving an ICI. Median duration of ICI therapy was 155 days. 223 Veterans received ICI monotherapy, with only 17(8%) having a reduction in PSA (median decline = 43%). 12 (5%) had PSA declines >30% (PSA30) which included 6 (3%) who had PSA reductions greater than 50% (PSA50). Median g-rates for ICI plus abiraterone (n = 20) or enzalutamide (n = 31) were 0.000689/d-1 and 0.002819/d-1, respectively, and were statistically insignificant compared to g-rates of matched cohorts receiving abiraterone (g = 0.000925/d-1, P = 0.73) or enzalutamide (g = 0.001929/d-1, P = 0.58) alone. Our data align with clinical trial data in PC, demonstrating limited benefit from ICI monotherapy and predicting no survival benefit from simultaneous abiraterone or enzalutamide with an ICI using g-rate.

Talazoparib in Patients With Solid Tumors With BRCA1/2 Mutation: Results From the Targeted Agent and Profiling Utilization Registry Study.

PURPOSE: The Targeted Agent and Profiling Utilization Registry Study is a phase II basket trial evaluating the antitumor activity of commercially available targeted agents in patients with advanced cancer and genomic alterations known to be drug targets. Results of a cohort of patients with various solid tumors with germline or somatic BRCA1/2 mutations treated with talazoparib are reported. METHODS: Eligible patients had advanced solid tumors, measurable disease (RECIST), Eastern Cooperative Oncology Group performance status 0-2, adequate organ function, and no standard treatment options. Patients with germline BRCA-mutated human epidermal growth factor receptor 2-negative locally advanced or metastatic breast cancer were not eligible for this study. Primary end point was disease control (DC) determined by investigator assessment of objective response (OR) or stable disease (SD) of at least 16 weeks duration (SD16+). The results were evaluated on the basis of a one-sided exact binomial test with a null DC rate of 15% versus 35% (power = 0.82; α = .10). Secondary end points were OR, progression-free survival, overall survival, duration of response, duration of SD, and safety. RESULTS: Twenty-eight patients (20 cancer types) with BRCA1/2 mutations were enrolled from December 2019 to September 2021 and collapsed into a single histology pooled cohort for analysis. All patients were evaluable for efficacy. One complete response, nine partial response, and six SD16+ were observed for DC and OR rates of 57% (one-sided 90% CI, 43 to 100) and 36% (95% CI, 19 to 56), respectively. The null hypothesis of a 15% DC rate was rejected (P < .001). Patients with OR had the following tumor types: breast (2), nonmelanoma skin, mesothelioma, stomach, uterus, non-small cell lung cancer, ovary, hepatocellular carcinoma, and pancreas. Thirteen patients had at least one grade 3-5 adverse event (AE) or serious AE at least possibly related to talazoparib. All were consistent with the drug label except bilirubin increase and hyponatremia (both grade 3 AEs). CONCLUSION: Talazoparib demonstrated antitumor activity in patients with advanced solid tumors and BRCA1/2 mutations, including cancer types for which poly ADP-ribose polymerase inhibitors are not yet US Food and Drug Administration-approved.

Influence of Cancer on COVID-19 Incidence, Outcomes, and Vaccine Effectiveness: A Prospective Cohort Study of U.S. Veterans.

PURPOSE: Coronavirus disease 2019 (COVID-19) has been a constant health threat since its emergence. Amongst risk factors proposed, a diagnosis of cancer has been worrisome. We report the impact of cancer and other risk factors in US Veterans receiving care at Veterans Administration (VA) Hospitals, their adjusted odds ratio (aOR) for infection and death, and report on the impact of vaccines on the incidence and severity of COVID-19 infections in Veterans without/with cancer. METHODS: We conducted a cohort study of US Veterans without/with cancer by mining VA COVID-19 Shared Data Resource (CSDR) data using the VA Informatics and Computing Infrastructure (VINCI). Our observation period includes index dates from 14DEC2020 to 25JAN2022, encompassing both the delta and omicron waves in the US. RESULTS: We identified 915,928 Veterans, 24% of whom were African Americans who had undergone COVID testing-688,541 were and 227,387 were not vaccinated. 157,072 had a cancer diagnosis in the preceding two years. Age emerged as the major risk factor, with gender, BMI, and (Elixhauser) comorbidity contributing less. Among veterans with solid tumors other than lung cancer, risks of infection and death within 60 days were comparable to Veterans without cancer. However, those with hematologic malignancies fared worse. Vaccination was highly effective across all cancer cohorts; the respective rates of infection and death after infection were 8% and 5% among the vaccinated compared to 47% and 10% in the unvaccinated. Amongst vaccinated, increased risk of infection was noted in both, Veterans with hematologic malignancy treated with chemotherapy (HR, 2.993, P < 0.0001) or targeted therapies (HR, 1.781, P < 0.0001), and in solid tumors treated with either chemotherapy (HR 2.328, 95%CI 2.075-2.611, P < 0.0001) or targeted therapies (HR 1.328, P < 0.0001) when compared to those not on treatment. CONCLUSIONS: Risk for COVID-19 infection and death from infection vary based on cancer type and therapies administered. Importantly and encouragingly, the duration of protection from infection following vaccination in Veterans with a diagnosis of cancer was remarkably like those without a cancer diagnosis. Veterans with hematologic malignancies are especially vulnerable, with lower vaccine effectiveness (VE).

Predictors of clonal evolution and myeloid neoplasia following immunosuppressive therapy in severe aplastic anemia.

Predictors, genetic characteristics, and long-term outcomes of patients with SAA who clonally evolved after immunosuppressive therapy (IST) were assessed. SAA patients were treated with IST from 1989-2020. Clonal evolution was categorized as "high-risk" (overt myeloid neoplasm [meeting WHO criteria for dysplasia, MPN or acute leukemia] or isolated chromosome-7 abnormality/complex karyotype without dysplasia or overt myeloid neoplasia) or "low-risk" (non-7 or non-complex chromosome abnormalities without morphological evidence of dysplasia or myeloid neoplasia). Univariate and multivariate analysis using Fine-Gray competing risk regression model determined predictors. Long-term outcomes included relapse, overall survival (OS) and hematopoietic stem cell transplant (HSCT). Somatic mutations in myeloid cancer genes were assessed in evolvers and in 407 patients 6 months after IST. Of 663 SAA patients, 95 developed clonal evolution. Pre-treatment age >48 years and ANC > 0.87 × 109/L were strong predictors of high-risk evolution. OS was 37% in high-risk clonal evolution by 5 years compared to 94% in low-risk. High-risk patients who underwent HSCT had improved OS. Eltrombopag did not increase high-risk evolution. Splicing factors and RUNX1 somatic variants were detected exclusively at high-risk evolution; DNMT3A, BCOR/L1 and ASXL1 were present in both. RUNX1, splicing factors and ASXL1 somatic mutations detected at 6 months after IST predicted high-risk evolution.

A novel approach to assess real-world efficacy of cancer therapy in metastatic prostate cancer. Analysis of national data on Veterans treated with abiraterone and enzalutamide.

BACKGROUND: With 1.3 million new cases in 2018 worldwide, prostate cancer remains a challenge. Development of novel therapies targeting the androgen pathway followed recognition of the continued importance of androgens in castrate-resistant prostate cancer. To assess abiraterone and enzalutamide efficacy we analyzed data from US Veterans Administration Medical Centers (VAMCs). METHODS: We used a novel method independent of assessment intervals and ideal for real-world analysis to estimate rates of tumor growth (g) and regression (d). FINDINGS: Using the VA Informatics and Computing Infrastructure, we collected data from 5,116 Veterans with castrate-resistant prostate cancer prescribed abiraterone, enzalutamide or both. We estimated values for g and d and demonstrated a correlation of g with overall survival (P < .0001). Abiraterone and enzalutamide slowed growth rates across age groups and across the entire VAMC system, although less so in Veterans previously treated with a taxane and those with Gleason grade group 5 tumors. Abiraterone and enzalutamide efficacy in first-line were comparable although abiraterone in first-line slowed growth rates significantly more in African Americans than in Caucasians; enzalutamide was a better salvage therapy. When abiraterone was first-line and g was low, switching to enzalutamide was associated with a faster g in 67%. INTERPRETATION: In the real-world g can be estimated using a novel analysis method indifferent to assessment intervals that correlates highly with OS. While we show excellent real-world outcomes with abiraterone and enzalutamide, 2 effective and tolerable therapies, our results in VAMCs suggest enzalutamide should follow abiraterone. Changing therapies may be detrimental and consideration should be given to continue monitoring of growth rates over time. Funding Support from the Prostate Cancer Foundation and the Blavatnik Family Foundation.

Eltrombopag Added to Standard Immunosuppression for Aplastic Anemia.

BACKGROUND: Acquired aplastic anemia results from immune-mediated destruction of bone marrow. Immunosuppressive therapies are effective, but reduced numbers of residual stem cells may limit their efficacy. In patients with aplastic anemia that was refractory to immunosuppression, eltrombopag, a synthetic thrombopoietin-receptor agonist, led to clinically significant increases in blood counts in almost half the patients. We combined standard immunosuppressive therapy with eltrombopag in previously untreated patients with severe aplastic anemia. METHODS: We enrolled 92 consecutive patients in a prospective phase 1-2 study of immunosuppressive therapy plus eltrombopag. The three consecutively enrolled cohorts differed with regard to the timing of initiation and the duration of the eltrombopag regimen (cohort 1 received eltrombopag from day 14 to 6 months, cohort 2 from day 14 to 3 months, and cohort 3 from day 1 to 6 months). The cohorts were analyzed separately. The primary outcome was complete hematologic response at 6 months. Secondary end points included overall response, survival, relapse, and clonal evolution to myeloid cancer. RESULTS: The rate of complete response at 6 months was 33% in cohort 1, 26% in cohort 2, and 58% in cohort 3. The overall response rates at 6 months were 80%, 87%, and 94%, respectively. The complete and overall response rates in the combined cohorts were higher than in our historical cohort, in which the rate of complete response was 10% and the overall response rate was 66%. At a median follow-up of 2 years, the survival rate was 97%; one patient died during the study from a nonhematologic cause. Marked increases in bone marrow cellularity, CD34+ cell number, and frequency of early hematopoietic progenitors were noted. Rates of relapse and clonal evolution were similar to our historical experience. Severe rashes occurred in two patients, resulting in the early discontinuation of eltrombopag. CONCLUSIONS: The addition of eltrombopag to immunosuppressive therapy was associated with markedly higher rates of hematologic response among patients with severe aplastic anemia than in a historical cohort. (Funded by the National Heart, Lung, and Blood Institute; ClinicalTrials.gov number, NCT01623167 .).

Adrenocortical Cancer: A Molecularly Complex Disease Where Surgery Matters.

The development of new therapies has lagged behind for rare cancers without defined therapeutic targets. Adrenocortical cancer is no exception. Mitotane, an older agent considered "adrenolytic," is used both to control symptoms in advanced disease and as adjuvant therapy after surgical resection. Molecular characterization of adrenocortical cancer has deepened our understanding of this genetically complex disease while identifying subgroups whose importance remains to be determined. Unfortunately, such studies have yet to demonstrate a therapeutic target for drug development, and to date, no targeted therapy has achieved meaningful outcomes. Consequently, first-line therapy for metastatic disease remains a combination regimen of etoposide, doxorubicin, and cisplatinum established in a randomized clinical trial. In addition to evaluating recent studies in adrenocortical cancer, we raise one critical clinical issue-the risk of peritoneal dissemination following laparoscopic resection of adrenocortical cancer. In a retrospective case series of 267 patients referred to the NCI for the treatment of recurrent or advanced adrenocortical cancer, we found extensive peritoneal dissemination in 25 of the 45 patients (55.6%) who had undergone laparoscopic resection, compared with only 7 of the 222 patients (3%) who had undergone an open resection (P < 0.0001). Although this has been debated in the literature, our data argue for an end to laparoscopic resection of adrenocortical cancers to avoid peritoneal dissemination, a complication of laparoscopy that is uniformly fatal. Clin Cancer Res; 22(20); 4989-5000. ©2016 AACR SEE ALL ARTICLES IN THIS CCR FOCUS SECTION, "ENDOCRINE CANCERS REVISING PARADIGMS".