Race Oncology has achieved a significant breakthrough in cancer drug development by isolating the active component of its lead therapeutic bisantrene and securing patent protection that could extend exclusivity until 2045. The Australian biotechnology company filed three new patent applications after discovering that historical formulations of the drug contained problematic chemical variations that may have compromised earlier clinical trials.
Chemical Discovery Resolves Decades-Old Formulation Issues
The company's research team determined that bisantrene, originally developed in the 1980s, consists of three light-sensitive photoisomers that rapidly interconvert when exposed to light. This instability created inconsistent drug mixtures with variable dosing and potentially reduced efficacy in past trials.
Race's scientists identified the (E,E)-bisantrene isomer as the component with significant anticancer activity and successfully isolated it to create a pure, stable formulation. CEO and Managing Director Dr. Daniel Tillett explained that this variability in the original formulation "led to inconsistent dosing and potentially reduced efficacy in earlier trials."
Strongest Patent Protection Secured
The patent applications cover the chemical structure, manufacturing, formulation, and use of the purified (E,E)-bisantrene isomer. Most significantly, the filings include a composition of matter patent—the strongest form of intellectual property protection available in pharmaceuticals.
"Being able to generate new composition of matter IP covering the active isomer of bisantrene fundamentally changes the commercial prospects of Race Oncology," Dr. Tillett stated. "We now expect to have 20 years of the strongest IP protection possible for the RC220 and RC110 formulations containing (E,E)-bisantrene."
Composition of matter patents secure exclusivity over the chemical structure of an active pharmaceutical ingredient regardless of synthesis or delivery method. Such patents are particularly valued in pharmaceutical licensing and acquisition deals, with global partners typically requiring at least 8-10 years of remaining patent life at product launch.
Clinical Program Benefits
The discovery directly applies to Race's current clinical programs. All recent and ongoing Race-sponsored trials, including two Phase 2 acute myeloid leukemia studies and the current Phase 1 solid tumor program, have utilized the purified (E,E)-bisantrene isomer.
The breakthrough also enables Race to revisit the original bisantrene formulation, which is already eligible for a Phase 3 trial in acute myeloid leukemia. This positioning significantly increases the company's clinical and commercial potential by building on decades of prior clinical experience while eliminating the formulation inconsistencies that may have limited earlier results.
Regulatory and Commercial Advantages
Race noted that regulators would not approve generic formulations based on older mixed-isomer versions of bisantrene due to dosing variability and the presence of inactive isomers. This regulatory barrier effectively prevents competitors from entering the market with generic versions of the historical formulation.
The company has requested accelerated examination of the new patents to support ongoing licensing discussions and commercial negotiations. Dr. Tillett emphasized that the findings "highlight the commercial value of undertaking new preclinical research on clinically established pharmaceutical assets."
Future Developments
Race plans to provide additional updates before its Annual General Meeting, including new trial data and scientific presentations. Dr. Tillett is scheduled to present on bisantrene's cardioprotective mechanism of action at a conference in Germany later this year.
The company will outline its findings in greater detail during a webinar scheduled for September 18, 2025, as it progresses plans for pivotal trials of its bisantrene formulations with enhanced patent protection and improved commercial positioning.
