Propella Therapeutics, Inc. (“Propella”), a private, clinical-stage biopharmaceutical company developing best-in-class oncology therapeutics, today announced that nonclinical data for its lead product candidate, PRL-02, will be featured at the 2022 ASCO Genitourinary (GU) Cancers Symposium, which is being held in San Francisco, CA from February 17-19, 2022. The poster will be presented by Dr. William Moore, President and Chief Executive Officer of Propella Therapeutics. Details on the poster presentation are provided below:

2022 ASCO Genitourinary (GU) Cancer SymposiumSession Information: Poster Session A: Prostate Cancer; February 17, 2022 from 11:30 AM-1:00 PM and 5:45 PM-6:45 PM PTAbstract Number: 160Abstract Title: “Abiraterone decanoate (PRL-02): Pharmacology of a single intramuscular (IM) depot injection compared to oral abiraterone acetate (AA) in intact male ratsPresenting Author: William Moore, Ph.D.

Dr. Moore will present results from nonclinical studies in male rodent models that evaluated the systemic exposures and pharmacologic activity (testosterone suppression, CYP17 enzyme activity) of single-dose, long-acting PRL-02 compared to daily oral abiraterone acetate (AA), the standard of care for metastatic prostate, at 7 and 14 days after treatment start.

Key Findings from Poster Presentation:

  • A single, intramuscular (IM) injection of PRL-02 produced large reductions in serum testosterone concentrations that were equivalent to those from daily abiraterone acetate at the clinical dose  
  • A single injection of PRL-02 produced complete inhibition of testicular CYP17 enzyme, 14 days following dose administration
  • PRL-02 produced higher concentrations of the highly active metabolite, Δ-4 abiraterone, than of abiraterone in the adrenal and testes
  • The persistent high concentrations of both Δ-4 abiraterone and abiraterone from PRL-02 in the adrenal and testes predict a long duration of clinical effect
  • Total abiraterone exposures were greater from IM PRL-02 than from oral AA in therapeutic target tissues (e.g., adrenal, testes, lymph, bone) whereas exposures from PO AA were greater in plasma and off-target tissues (e.g., liver, brain)
  • The relatively greater on-target to off-target exposures of abiraterone equivalents from IM PRL-02 compared to PO AA may provide an improved therapeutic index, which could lead to an improved safety and efficacy profile in patients with advanced prostate cancer

According to Dr. William Douglas Figg, Sr, Head of the Clinical Pharmacology Program and Deputy Chief of the Genitourinary Malignancies Branch of the National Cancer Institute, the federal government's principal agency for cancer research and training and a PRL-02 development partner, “These data from the male rat study, in combination with previous data from the gold standard, non-human primate model, further justify the ongoing clinical development of PRL-02 depot for the treatment of prostate cancer.”

“The non-clinical data we are presenting at this year’s ASCO GU conference continue to support the potential for PRL-02 to become the best-in-class androgen biosynthesis inhibitor for the treatment of advanced prostate cancer and other hormone-driven cancers,” said Dr. Moore. “The results obtained to date with PRL-02 reflect the potential advantages our unique platform, which combines outstanding medicinal chemistry with lymphatic delivery, can provide; that is, highly active oncology drug candidates that also have a high safety margin. Thus far, we are very encouraged with the evolving therapeutic profile of PRL-02, as these data suggest that intramuscular delivery is leading to increased bioavailability to the target tissues where CYP17 enzyme is expressed, a reduced impact on the liver, and an improved therapeutic index relative to abiraterone acetate. We look forward to providing an update from our ongoing Phase 1/2 study of PRL-02 later this year.”    

PRL-02 is being evaluated in an ongoing Phase 1/2a study (NCT04729114) for patients with advanced prostate cancer. The Phase 1 portion is an open-label, multi-center, dose-escalation study designed to assess the safety, tolerability, pharmacokinetics, and preliminary clinical activity of PRL-02 and establish a recommended dose for the Phase 2a portion. The recommended Phase 2 dose will be selected in Q2 2022 based upon pharmacokinetic, safety, clinical pharmacology, and efficacy results.

About ASCO GU Cancer Symposium

The ASCO Genitourinary (GU) Cancers Symposium is a three-day scientific and educational meeting designed to provide attendees with in-depth, multidisciplinary analysis of the most timely topics in the study, diagnosis, and treatment of GU malignancies. All members of the cancer care and research community will benefit from the Symposium's exploration of the latest science in the field and its clinical application.

About Metastatic Prostate Cancer

Prostate cancer is the most common non-skin cancer in men, and the second leading cause of cancer death, developing most often in older men. Metastatic disease occurs when prostate cancer cells travel through the lymphatic system or blood stream to other organs and tissues such as lymph nodes, bone, liver, and lungs. While early or localized prostate cancer remains highly curable, advanced prostate cancer remains difficult to treat, with a 5-year survival rate of only 30%. Although there are several pharmacological treatment options for metastatic prostate cancer, the reduction of androgen activity remains the most effective approach.    

About PRL-02

PRL-02 is a next generation androgen biosynthesis inhibitor being developed for the treatment of prostate cancer. The only androgen biosynthesis inhibitor approved for the treatment of prostate cancer blocks the CYP17 enzyme that is required for the biosynthesis of androgens, including testosterone. A large body of both historic and modern data support a role for androgens in prostate cancer pathogenesis and progression. PRL-02 is a patented prodrug of abiraterone designed for the lymphatic targeting of tissues and tumors that express the CYP17 enzyme. PRL-02 is an intramuscular depot that was engineered to locally release the precise concentration of abiraterone needed to continuously block CYP17 enzyme while avoiding adverse liver and drug-drug interaction effects.

About Propella Therapeutics Inc.

Propella Therapeutics is a biopharmaceutical company that has developed a platform that combines lymphatic targeting with a medicinal chemistry optimization process to create best- or first-in-class oncology drugs starting from active moieties that have validated MOAs and biological targets but suffer efficacy limitations due to low bioavailability and / or safety concerns due to overexposure to non-target tissues. Lymphatic targeting enables therapies to be delivered directly to therapeutic target tissues, thereby bypassing plasma compartment safety and efficacy limitations and first-pass liver effects. This approach provides increased bioavailability to tissues of interest including lymph nodes and bone metastatic sites, increased pharmacological activity, reduced liver effects, and an improved therapeutic index. Propella is currently in the Phase 1 portion of a Phase 1/2a study of its lead product candidate, PRL-02, for the treatment of metastatic prostate cancer. The privately held development-stage company, based in Pittsboro, N.C., is dedicated to meeting the needs of cancer patients currently underserved by existing standards of care.

Media and Investor Contact:Brendan Griffin, Chief Financial 855-225-6378