Rgenta Therapeutics announced that the U.S. Food and Drug Administration has granted Orphan Drug Designation to RGT-61159 for the treatment of adenoid cystic carcinoma (ACC), marking a significant regulatory milestone for the clinical-stage biotechnology company's lead oncology program. The designation recognizes the drug's potential to address a critical unmet medical need in treating this rare and aggressive cancer.
Novel Mechanism Targets Previously Undruggable Oncogene
RGT-61159 represents a breakthrough approach in cancer therapeutics as a potent and selective orally available small molecule inhibitor of MYB through RNA splicing modulation. The drug is designed to specifically modulate splicing of the transcription factor MYB, resulting in inhibition of the oncogenic MYB protein and potential cell death of cancer cells that overexpress this protein.
"As a potent and selective inhibitor of MYB, RGT-61159 is designed to unlock the therapeutic potential of this historically undruggable target and address the root cause of ACC and several other aggressive cancers," said Travis Wager, Ph.D., co-founder and chief scientific officer of Rgenta Therapeutics.
MYB acts as a master regulator of cell proliferation, self-renewal, and differentiation processes. Its aberrant expression has been demonstrated across multiple forms of human cancer including adenoid cystic carcinoma, acute myeloid leukemia, T-cell acute lymphoblastic leukemia, colorectal cancer, small cell lung cancer, and breast cancer.
Current Clinical Development Program
The company is currently evaluating RGT-61159 in an ongoing multi-center, open-label Phase 1a/b clinical trial in patients with advanced relapsed or refractory ACC or colorectal cancer. The study is designed to evaluate safety, tolerability, pharmacokinetics, target engagement, and clinical efficacy of the investigational drug.
"Our ongoing Phase1a/b clinical trial of RGT-61159 is designed to evaluate its safety and tolerability as well as pharmacokinetics, target engagement, and clinical efficacy in patients with relapsed or refractory ACC or colorectal cancer," said Simon Xi, Ph.D., co-founder and chief executive officer of Rgenta. "We also plan to broaden this program and initiate a new Phase 1/2 study of RGT-61159 in adults with AML/high risk myelodysplastic syndromes."
Addressing Critical Unmet Medical Need
Adenoid cystic carcinoma affects approximately 200,000 people worldwide, including 11,000 in the United States. Despite being classified as a rare cancer, ACC is the second most common cancer type arising in the salivary gland and presents as an aggressive malignancy with a tendency to infiltrate surrounding nerves and metastasize to distant sites.
The disease is characterized by overactivation of the MYB oncogene, which has been described as a hallmark of ACC and is noted in over 90% of cases. Current treatment options are extremely limited and may include surgery and/or radiation, which often fail to control local tumor recurrence and distant metastases. Critically, there are no effective targeted therapies available for patients with recurrent and/or metastatic disease.
Regulatory Benefits and Market Implications
The FDA's Orphan Drug Designation program provides orphan status to therapies intended for the treatment, diagnosis, or prevention of rare diseases that affect fewer than 200,000 people in the United States. This designation is granted to medicinal products that represent a significant benefit over existing treatments and are intended for life-threatening or chronically debilitating diseases.
The designation provides substantial regulatory and commercial benefits, including tax credits for qualified clinical testing, waiver or partial payment of FDA application fees, and seven years of market exclusivity if the drug receives approval.
"Receiving this designation for RGT-61159 is an important milestone for Rgenta, underscoring the significant unmet medical need for treatments for ACC and validating our ongoing commitment to pursuing potential first- and best-in-class medicines for life altering diseases," Xi noted.
Innovative RNA-Targeting Platform
Rgenta Therapeutics is pioneering the development of a new class of oral small molecules targeting RNA and RNA regulation for oncology and neurological disorders. The company's proprietary platform mines massive genomics data to identify targetable RNA processing events and design small-molecule glues to modulate interactions among the spliceosome, regulatory proteins, and RNAs.
This unique approach is designed to unlock the therapeutic potential of historically undruggable targets in human diseases, with RGT-61159 serving as a lead example of the platform's capabilities in addressing previously intractable oncology targets.
