Phoenix Molecular Designs (PhoenixMD), a clinical stage biopharmaceutical company dedicated to developing precise cancer therapeutics, today announced the completion of patient enrollment and dosing of PMD-026 in their Phase 1b monotherapy clinical trial. The successful completion of patient enrollment in this Phase 1/1b trial is an important step forward for PhoenixMD as they advance PMD-026 into Phase 2 combination trials for triple negative breast cancer (TNBC) and hormone-positive breast cancer.
Breast cancer is now the most commonly-diagnosed cancer across the globe, and despite continued advancements in the treatment of metastatic breast cancer, more than 43,000 women are estimated to die from the disease in 2022 in the U.S.1,2. Moreover, for TNBC, a subtype of breast cancer with less favorable outcomes, there are limited targeted cancer therapies based on a biomarker selection3. With PMD-026, PhoenixMD is committed to changing the odds in helping patients live longer.
"This is an important and exciting day for PhoenixMD. The completion of patient enrollment in our Phase 1b clinical trial brings us closer to our ultimate goal of developing a therapeutic that will bring a clinically meaningful improvement to the lives of thousands of people living with TNBC," said Dr. Sandra E. Dunn, Founder and CEO of Phoenix Molecular Designs. "We are making hope a reality as the PhoenixMD team has developed the first uniquely-engineered kinase inhibitor for TNBC based on RSK2 as a biomarker for patient selection."
PhoenixMD's lead asset, PMD-026, is a proprietary first-in-class orally-available RSK (kinase) inhibitor that was developed as a potential solution to attack difficult to treat cancers such as TNBC. RSK has a unique mechanism of disease that remains active despite patients failing chemotherapy, hormone therapy, and targeted therapies. By targeting RSK, PhoenixMD aims to develop more durable approaches to cancer treatment in the future.
The Company's Phase 1/1b clinical trial was conducted at nine leading cancer centers across the United States. The primary endpoints were to ensure safety and tolerability and establish the recommended Phase 2 dosing schedule of PMD-026 in patients. A major secondary endpoint was to assess whether the level of RSK2 expression in tumors was indicative of better patient outcomes using the companion diagnostic. A total of 41 patients were dosed with PMD-026 twice daily continuously.
"Our precision medicine approach has always been patient-centred with the aim of developing a therapeutic that can be easy for patients to take with limited side effects. Throughout the 14 month trial, the safety pro PMD-026 remains well-tolerated. PMD-026 does not cause hair loss, peripheral neuropathy, or decreased blood counts, which are common side effects of breast cancer therapies," said Andrew Dorr, M.D., Chief Medical Officer of Phoenix Molecular Designs. "This positions PMD-026 as a drug that can easily be combined with other drugs. I look forward to the exciting combination trials PhoenixMD has planned ahead."
"Our goal to use our companion diagnostic to select patients who have the best chance to respond to PMD-026 treatment has come one step closer. Based on interim data, the retrospective analysis of the RSK2 tumor levels in this study indicated that patients with high RSK2 benefited from PMD-026 better than patients with lower RSK2 tumor levels. Breast cancer patients taking PMD-026 with high RSK2 tumor expression had three times longer progression-free survival (PFS) compared to patients with low RSK2. PFS in the RSK2 high group was 3.3 months which is nearly double that of chemotherapy historical controls in an earlier line of treatment4. This was remarkable considering patients had a median of five prior lines of therapy. We look forward to the topline data release from the Phase 1b trial tentatively in the second quarter of this year," said Dr. Dunn. "I would like to thank all of the patients and their families for their involvement and commitment in this trial, and to the investigators and our outstanding team, whose dedication and groundbreaking expertise have let us achieve these important high points."
About PMD-026
PhoenixMD's lead candidate, PMD-026, is the first RSK inhibitor being developed for the treatment of TNBC. It is a pill that is convenient for patients as opposed to intravenous delivery, the mode most commonly used to deliver chemotherapy. PMD-026 was designed for TNBC because RSK2 was specifically identified as the key kinase that drives the growth of this breast cancer subtype5, 6. PMD-026 is well-tolerated in breast cancer patients and can stop tumor growth for up to 5 months based on Phase 1 data. PFS in women with TNBC is three times longer for patients that express high levels of RSK2 activation as compared to those with low RSK2 activation. Preclinical data shows PMD-026 has the potential to be a platform technology for chemotherapy, hormone therapy and/or immunotherapy sensitization for a wide range of refractory cancers in the future.
About Phoenix Molecular Designs
PhoenixMD is a privately-held, clinical-stage biopharmaceutical company designing precise cancer therapeutics and companion diagnostics by targeting kinases, a class of highly druggable enzymes to treat a wide range of oncology indications. PhoenixMD is focused on developing first-in-class inhibitors against RSK, an important drug target for cancer, heart disease, and inflammation. The company's leadership team boasts previous expertise in developing FDA-approved and marketed drugs for breast cancer. Due to PhoenixMD's emerging leadership in kinase inhibition, the company has partnered with well-recognized government and academic research institutions, including the National Cancer Institute, MD Anderson Cancer Center, Kyushu University (Japan) and the University of Tuebingen (Germany). PhoenixMD has clinical headquarters in San Diego, CA, and preclinical operations in Vancouver, BC.
