FDA Authorizes IND Application for 177Lu-rhPSMA-10.1 for Metastatic Castration-Resistant Prostate Cancer

The FDA has cleared an investigational new drug (IND) application for ¹⁷⁷Lu-rhPSMA-10.1 as a potential therapeutic option for patients with metastatic castration-resistant prostate cancer (mCRPC), according to an announcement from Blue Earth Therapeutics.¹

The authorization allows for the clinical-stage company to initiate a open-label, multicenter, phase 1/2 trial designed to examine the safety, tolerability, dosimetry, and antitumor activity of the next-generational radiopharmaceutical in this patient population.

“Clearance to proceed with this first clinical study for ¹⁷⁷Lu-rhPSMA-10.1 marks an exciting milestone for our new company, Blue Earth Therapeutics, and the patients with cancer that we hope to serve,” David E. Gauden, DPhil, chief executive officer of Blue Earth Therapeutics, stated in a press release. “We consider ¹⁷⁷Lu-rhPSMA-10.1 to be a next-generation prostate-specific membrane antigen [PSMA] therapy with the potential to be best-in-class.”

Radiohybrid PSMA (RhPSMA) compounds are comprised of 3 distinct domains. This first includes a PSMA-targeted receptor ligand that binds to and is internalized by prostate cancer cells; specifically, the ligand attaches to 2 labelling moieties that could be radiolabeled with 18F for PET imaging or isotopes like ¹⁷⁷Lu or 225Ac. This technology is hypothesized to potentially play a key role in the future management of patients with prostate cancer and provide the opportunity for precision medicine in this disease. To date, rhPSMA compounds have not received regulatory approval.

“¹⁷⁷Lu-rhPSMA-10.1 is the result of a careful optimization process which aimed to maximize therapeutic index by delivering high radiation doses to prostate cancer lesions while sparing normal tissues wherever possible,” Gauden added.

The phase 1 portion of the trial is slated to examine the safety, tolerability, and dosimetry of several cycles of ¹⁷⁷Lu-rhPSMA-10.1 in patients with PSMA-positive mCRPC who had experienced disease progression after prior treatment. Data from the phase 1 part of the research will be leveraged to identify the recommended treatment regimen that will be further evaluated in the phase 2 component.

The phase 1 study will be performed at clinical sites throughout the United States, and additional sites are anticipated to be added in both the United States and Europe for the phase 2 portion of the trial.

“We look forward initially to applying our proven radiopharmaceutical development expertise in advancing ¹⁷⁷Lu-rhPSMA-10.1, and, over time, developing a pipeline of additional oncology therapeutics to help address significant unmet patient needs,” Gauden concluded.

Reference

1. Blue Earth Therapeutics announces US FDA clearance for investigational new drug (IND) application for 177Lu-rhPSMA-10.1 for treatment of prostate cancer. News release. Blue Earth Therapeutics; April 12, 2022. Accessed April 12, 2022. https://bit.ly/3JExLRc