Defence Therapeutics' Accum-Kadcyla Shows 20-Fold Efficacy Boost in HER2-Positive Breast Cancer Models
Key Insights
Defence Therapeutics (search) reported that Accum®-Kadcyla demonstrated 20-fold higher anti-tumor efficacy compared to Kadcyla® alone at equivalent doses in HER2-positive breast cancer (search) mouse models.
The enhanced ADC achieved near-complete tumor response with 100% animal survival and no toxicity signs, potentially enabling dose reduction and improved safety profiles.
These breakthrough results could shift ADC therapies from second-line to first-line treatments, with Defence planning to expand studies and engage pharmaceutical partners.
Defence Therapeutics (search) has announced breakthrough preclinical results for its Accum®-Kadcyla, a novel version of Genentech/Roche's marketed ADC Kadcyla® (ado-trastuzumab emtansine), demonstrating a remarkable 20-fold increase in anti-tumor efficacy in HER2-positive breast cancer (search) models. The findings, presented at the World ADC Conference in San Diego, could potentially transform current treatment paradigms by enabling the shift of ADC therapies from second-line to first-line treatments.
Dramatic Efficacy Enhancement in Preclinical Studies
In comparative in vivo studies using mouse models of HER2-positive breast cancer (search), Accum®-Kadcyla showed approximately 20-fold higher anti-tumor efficacy than Kadcyla® alone when administered at the same dose of 0.5 mg/kg. The enhanced ADC significantly halted tumor growth, resulting in durable and near-complete responses in most mice, while Kadcyla® at the same dose had no effect on tumor growth.
Critically, 100% of animals survived throughout the study duration with no signs of toxicity, demonstrating excellent tolerability of the treatment. This safety profile is particularly significant given the enhanced potency achieved.
Addressing Key ADC Limitations
The results validate Defence's proprietary Accum® platform's ability to overcome endosomal entrapment, a known bottleneck in ADC performance. By dramatically enhancing intracellular delivery and potency of ADCs, the technology enables more efficient drug release and tumor killing, even at lower doses.
Dr. Maxime Parisotto, Chief Scientific Officer of Defence Therapeutics (search), commented: "These results further validate the power of Accum® as a transformative technology for ADCs. By amplifying the potency of a clinically proven ADC like Kadcyla® by 20 times at the same dose, we demonstrate that Accum® can unlock a new generation of safer and more effective targeted therapies for cancer (search) patients."
Clinical Implications and Patient Benefits
The ability to achieve equivalent or superior efficacy at reduced doses translates into potential reductions in toxicity and side effects, addressing one of the main limitations of current ADC therapies. This advancement could enable the transition of current second-line treatments to first-line therapy options, offering significant benefits to patients with HER2-positive breast cancer (search).
The enhanced therapeutic window provided by Accum®-Kadcyla's improved safety and efficacy profile could expand treatment options for patients who may not currently be candidates for ADC therapy due to tolerability concerns.
Strategic Development Plans
Following these promising results, Defence Therapeutics (search) plans to expand its Accum®-ADC program to additional HER2 (search)-positive and HER2-low tumor models. The company is also advancing discussions with potential pharmaceutical partners to further develop and commercialize the technology.
Defence Therapeutics (search), a publicly-traded biotechnology company, specializes in developing next-generation ADC products using its proprietary Accum® technology platform, which enables precision delivery of ADCs in their intact form to target cells, resulting in increased efficacy and potency against cancer (search).