TAVT-45 Demonstrates Therapeutic Equivalence to Abiraterone Acetate Tablets in Metastatic Prostate Cancer

TAVT-45 granules for oral suspension (abiraterone acetate) yielded positive topline results and demonstrated therapeutic equivalence to abiraterone tablets (Zytiga) in the treatment of patients with metastatic castration-resistant prostate cancer (mCRPC) and metastatic castration-sensitive prostate cancer (mCSPC), according to a press release from Tavanta Therapeutics on data from the phase 3 TAVT45C02 trial (NCT04887506).

The primary end point of the trial was reached, as TAVT-45 and abiraterone tablets yielded comparable serum testosterone levels at days 9 and 10 of treatment vs the tablets. Additionally, the key secondary end point of reducing prostate-specific antigen levels by 50% or more from baseline did not show a statistical difference between the treatment arms. Moreover, the safety profile of TAVT-45 was consistent with those reported when abiraterone tablets were used.

“It is encouraging to see a familiar efficacy and safety profile for TAVT-45, which is consistent with data established for abiraterone as a standard of care in the treatment of metastatic prostate cancer,” study investigator Kenneth M. Kernen, MD, a partner at the Michigan Institute of Urology, said in the press release. “The positive results from this clinical study further support and validate the use of TAVT-45 as a novel, oral, easy-to-drink formulation of abiraterone acetate.”

TAVT-45 is an alternative formulation of abiraterone acetate designed for the treatment of metastatic prostate cancer by producing an oral suspension when reconstituted with water or juice. The agent may benefit a population of patients who have dysphagia or difficulty swallowing tablets, potentially increasing the bioavailability of abiraterone and allowing a lower dose to be taken.

Investigators of the global, randomized, multi-center, open-label phase 3 TAVT45C02 trial evaluated the pharmacokinetics, efficacy, and safety of TAVT-45 and abiraterone tablets in combination with prednisone among patients with mCRPC or high-risk mCSPC.

Patients were randomly assigned to either receive 250 mg of TAVT-45 granules for oral suspension twice a day or 500 mg of abiraterone tablets once daily. Patients in both arms also received 5 mg of prednisone once per day if they had mCSPC or twice a day if they had mCRPC.

Patients 18 years and older with a pathologically confirmed diagnosis of adenocarcinoma of the prostate were eligible to enroll on the trial. Additional inclusion criteria included having received ongoing therapy with a gonadotropin releasing hormone agonist or antagonist, having an ECOG performance status of 0 to 2 at screening, normal organ function with acceptable laboratory values, and a life expectancy of at least 6 months at screening.

Patients who initiated bisphosphonate or denosumab therapy 4 weeks prior to beginning treatment were unable to enroll on the study. Patients were also unsuitable for enrollment if they had therapy with estrogen 4 weeks before the start of study treatment, known central nervous system metastases, a history of adrenal gland dysfunction, or a history of other malignancies within the 2 previous years.

“Approximately 20 to 30 percent of [patients with] cancer, including many patients with prostate cancer, have difficulty swallowing pills and capsules. We believe these patients may benefit from an alternate formulation like TAVT-45 that would allow them to take their much-needed medications in an easier-to-take formulation,” Andreas Maetzel, MD, PhD, chief medical officer at Tavanta Therapeutics, concluded.

Reference

Tavanta Therapeutics announces positive top-line results from pivotal phase 3 Trial of TAVT-45 for the treatment of metastatic prostate cancer. News release. Tavanta Therapeutics. January 5, 2023. Accessed January 9, 2023. bit.ly/3XmeZFL