Pfizer Announces Positive Topline Results from Phase 3 TALAPRO-2 Trial
- Category: Small Molecules
- Published on Tuesday, 04 October 2022 15:35
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- TALZENNA® first PARP inhibitor to demonstrate clinical benefit in combination with XTANDI® in metastatic castration-resistant prostate cancer (mCRPC)
- Study achieves primary endpoint of radiographic progression-free survival
- Robust, highly consistent efficacy demonstrated in mCRPC both with or withouthomologous recombination repair gene mutations
NEW YORK, NY, USA I October 04, 2022 I Pfizer Inc. (NYSE: PFE) today announced positive topline results from the Phase 3 TALAPRO-2 study of TALZENNA® (talazoparib), an oral poly ADP-ribose polymerase (PARP) inhibitor, in combination with XTANDI® (enzalutamide) compared to placebo plus XTANDI in men with metastatic castration-resistant prostate cancer (mCRPC), with or without homologous recombination repair (HRR) gene mutations. The study met its primary endpoint with a statistically significant and clinically meaningful improvement in radiographic progression-free survival (rPFS) compared with placebo plus XTANDI. The results of the primary endpoint exceeded the pre-specified hazard ratio of 0.696.
Results showed a trend toward improved overall survival, a key secondary endpoint, at the time of the analysis, but these data are not yet mature. Benefits were also observed in other secondary endpoints, including investigator assessed rPFS, prostate specific antigen (PSA) response, time to PSA progression, and overall response rate. Other secondary endpoints are being analyzed. At the time of topline analysis, the safety of TALZENNA plus XTANDI were generally consistent with the known safety profile of each medicine.
“XTANDI is a global standard of care, with overall survival demonstrated in mCRPC, non-metastatic CRPC, and metastatic castration-sensitive prostate cancer (mCSPC),” said Chris Boshoff, M.D., Ph.D., Chief Development Officer, Oncology and Rare Disease, Pfizer Global Product Development. “We are very pleased with the strong findings from TALAPRO-2, and although no definitive conclusions can be made across trials, the rPFS appears to be the longest observed in a randomized trial in this setting. These data highlight the potential for TALZENNA in combination with XTANDI, if approved, to become a new standard of care for mCRPC, irrespective of HRR gene mutation status. We look forward to discussing these data with global health authorities.”
“These exciting results from TALAPRO-2 underscore our long-standing commitment to men living with prostate cancer and delivering the next scientific breakthroughs,” said Suneet Varma, Global Oncology and U.S. President, Pfizer. “Based on these compelling combination data with XTANDI, we believe TALZENNA in prostate cancer may become the next potential blockbuster opportunity in our leading Pfizer Oncology portfolio, subject to regulatory approval.”
Detailed results from TALAPRO-2 will be submitted for presentation at a near-term medical congress. These data will also be shared with global regulatory authorities to potentially support a regulatory filing.
TALZENNA or the combination of TALZENNA plus XTANDI have not been approved by any regulatory agency for the treatment of mCRPC. In addition to the TALAPRO-2 trial, the combination of TALZENNA plus XTANDI is being investigated in the TALAPRO-3 trial (NCT04821622), a global, randomized, double-blind, placebo-controlled Phase 3 study in men with HRR-deficient mCSPC.
About Metastatic Castration-Resistant Prostate Cancer
Metastatic castration-resistant prostate cancer (mCRPC) is a cancer that has spread beyond the prostate gland and has progressed despite medical or surgical treatment to lower testosterone. Approximately 10%–20% of prostate cancer patients develop mCRPC within 5−7 years of diagnosis,1 and in the U.S., in 2020, approximately 60-90 thousand cases of the three million prostate cancer cases were mCRPC.2
The Phase 3 TALAPRO-2 trial is a two-part, two-cohort, multicenter, randomized, double-blind, placebo-controlled study that enrolled 1,095 patients with mCRPC (with no systemic treatments initiated after documentation of mCRPC) at sites in the U.S., Canada, Europe, South America, and the Asia-Pacific region. The study included two patient cohorts: all-comers (n=750) and those with HRR mutations (HRRm; n=380). Patients on androgen deprivation therapy (ADT) or who had bilateral orchiectomy in the trial were randomized to receive TALZENNA 0.5 mg/day plus XTANDI 160mg/day, or placebo plus XTANDI 160 mg/day.
The primary endpoint of the trial is radiographic progression-free survival (rPFS), defined as the time from the date of randomization to first objective evidence of radiographic progression by blinded independent review, or death, whichever occurs first, in both cohort 1 (all-comers) and cohort 2 (those with HRRm). The trial is still ongoing for cohort 2. Secondary endpoints include overall survival, objective response rate, duration of response and PSA response.
About TALZENNA® (talazoparib)
TALZENNA (talazoparib) is an inhibitor of PARP enzymes, which play a role in the DNA damage repair response. Preclinical studies have demonstrated that TALZENNA blocks PARP enzyme activity and traps PARP at the site of DNA damage, leading to decreased cancer cell growth and cancer cell death. TALZENNA is being evaluated in several ongoing clinical trials in prostate cancer, as well as other novel combinations with targeted therapies in various solid tumors. TALZENNA was approved by the U.S. Food and Drug Administration in 2018 for the treatment of adult patients with deleterious or suspected deleterious germline breast cancer susceptibility gene (BRCA)-mutated (gBRCAm) human epidermal growth factor receptor 2 (HER2)-negative locally advanced or metastatic breast cancer.
Indication in the U.S.
TALZENNA (talazoparib) is indicated for the treatment of adult patients with deleterious or suspected deleterious germline breast cancer susceptibility gene (BRCA)-mutated (gBRCAm) human epidermal growth factor receptor 2 (HER2)-negative locally advanced or metastatic breast cancer. Select patients for therapy based on an FDA-approved companion diagnostic for TALZENNA.
About XTANDI® (enzalutamide) and Important Safety Information
XTANDI (enzalutamide) is an androgen receptor inhibitor indicated in the U.S. for the treatment of patients with castration-resistant prostate cancer (CRPC) and metastatic castration-sensitive prostate cancer (mCSPC).
Overall survival benefit has been observed in patients treated with XTANDI in mCRPC, nmCRPC, and mCSPC
Please see Full Prescribing Information
for additional safety information.
About Pfizer Oncology
At Pfizer Oncology, we are committed to advancing medicines wherever we believe we can make a meaningful difference in the lives of people living with cancer. Today, we have an industry-leading portfolio of 24 approved innovative cancer medicines and biosimilars across more than 30 indications, including breast, genitourinary, colorectal, blood and lung cancers, as well as melanoma.
About the Pfizer/Astellas Collaboration
In October 2009, Medivation, Inc., which is now part of Pfizer (NYSE: PFE), and Astellas (TSE: 4503) entered into a global agreement to jointly develop and commercialize enzalutamide. The companies jointly commercialize XTANDI in the United States and Astellas has responsibility for manufacturing and all additional regulatory filings globally, as well as commercializing XTANDI outside the United States.
1 Kirby M, et al. Int J Clin Pract. 2011;11:1180-1192.
2 ScherHI, et al. PLoSOne. 2015;10:e0139440.