Enrollment Complete in TAVT45CO2 Study of TAVT-45 in mCSPC and mCRPC

The phase 3 TAVT45CO2 study investigating TAVT-45 in patients with metastatic castrate-sensitive prostate cancer and metastatic castrate-resistant prostate cancer has finished enrollment.

The phase 3 TAVT45CO2 study (NCT04887506) of TAVT-45 in patients with metastatic castrate-sensitive prostate cancer (mCSPC) and metastatic castrate-resistant prostate cancer (mCRPC) has completed enrollment, according to Tavanta Therapeutics.1

TAVT-45 is an enhanced formulation of abiraterone acetate (Zytiga) being used as treatment in metastatic prostate cancer. Designed as an easy-to-consume oral suspension, the granule is looking to offer patients an alternate option to abiraterone acetate, especially for patients with dysphagia who have difficulty swallowing pills and capsules.

"The current standard of care treatment for metastatic prostate cancer requires patients to ingest multiple large tablets, and under strict fasting conditions due to the risk of increased and highly variable abiraterone exposures with food," said Kenneth M. Kernen, MD, study investigator and partner in the Michigan Institute of Urology, in the press release. "Dysphagia is an issue for many and it occurs more frequently in elderly patients. If TAVT-45 proves successful in this trial, clinicians may soon have access to an alternative, easy-to-drink formulation of abiraterone acetate with improved bioavailability and reduced systemic variability, which may ultimately help patients achieve better clinical outcomes."

In the global, randomized, multicenter, open-label, phase 3 trial, investigators aim to evaluate the pharmacodynamic effect and the safety profile of TAVT-45 granules compared with abiraterone acetate in combination with prednisone in patients with mCSPC and mCRPC.2

One hundred seven patients have been enrolled in the trial with randomization stratified by prostate cancer population (mCSPC vs mCRPC) and baseline testosterone defined as 10 ng/dL and greater vs 10 ng/dL and less. Patients will be randomized in a 1:1 ratio to receive either TAVT-45 1 administered twice a day including 250 mg abiraterone acetate plus prednisone at 5 mg once or twice daily, or reference abiraterone acetate administered once daily as 2 x 500 mg abiraterone acetate tablets in addition to 5 mg of prednisone once or twice a day.

Enrollment was open to male patients aged at least 18 years or older with a pathologically confirmed adenocarcinoma of the prostate who had either mCSPC or mCRPC. Ongoing therapy with a gonadotropin releasing hormone agonist or antagonist and a serum testosterone level < 50 ng/dL at the time of screening were allowed as well as prior treatments and/or surgery for prostate cancer.

Other eligibility requirements included an ECOG performance status of 0-2, normal organ function with acceptable initial laboratory values within the screening period, and a life expectancy of at least 6 months at screening.

The primary end point of the trial is to evaluate testosterone levels with secondary end points including the percent of subjects with prostate-specific antigen (PSA)-50 response over 28, 56, and 84 days, testosterone levels, PSA levels, trough concentrations of abiraterone, and pharmacokinetics (PK).

The study aims to characterize the multiple-dose PK profile of TAVT-45 Granules and investigate the safety and efficacy of this new formulation of TAVT-45 in this patient population. Topline results for the study are expected to be released by the end of this year.

“We look forward to completing the dosing and follow-up phases of the study. As we work to complete this registrational trial for TAVT-45, we will begin preparing for the submission of our new drug application to the FDA in the third quarter of 2023, while also evaluating strategic options for [the] commercialization of TAVT-45," said Lynne Powell, chief executive officer of Tavanta Therapeutics, in the press release.

References:
  1. Tavanta Therapeutics Announces Completion of Enrollment in Pivotal Phase 3 Trial of TAVT-45 for the Treatment of Metastatic Prostate Cancer. News release. Tavanta Therapeutics. August 1, 2022. Accessed August 2, 2022. https://prn.to/3zNYuJr
  2. TAVT-45 (abiraterone acetate) granules in patients with prostate cancer. ClinicalTrials.gov. Updated August 1, 2022. Accessed August 2, 2022. https://clinicaltrials.gov/ct2/show/NCT04887506?term=tavanta&draw=2&rank=1