Theralase's data point to enhanced cancer cell kill

Mr. Roger DuMoulin-White reports LIGHT-ACTIVATED RUVIDAR AND INTERFERON DEMONSTRATE ENHANCED EFFICACY Recent in vitro data have demonstrated an enhanced bladder cancer cell kill, when Theralase Technologies Inc.'s light-activated Ruvidar is combined with recombinant human interferon alpha-2b. In preclinical research, T24 human bladder cancer cells were treated with two concentrations of light-activated Ruvidar or left untreated. After activation with green light, cells were exposed to increasing doses of rhIFNalpha2b. The effectiveness of the treatment was assessed by how many cancer cells were killed 48 hours posttreatment. Key findings include: Light-activated Ruvidar induced dose-dependent cytotoxicity in T24 human bladder cancer cells; rhIFNalpha2b induced dose-dependent cytotoxicity in T24 bladder cancer cells; The combination of light-activated Ruvidar with rhIFNalpha2b resulted in 50 to 65 per cent higher total cell kill compared with no light-activated Ruvidar; Enhanced cytotoxic effects were observed across increasing concentrations of rhIFNalpha2b, suggesting a strong additive effect. Light-activated Ruvidar works by directly killing tumour cells causing them to die in a way that helps the immune system recognize the cancer. This process releases tumour-specific signals that activate both the body's immediate (innate) and long-term (adaptive) immune responses. Interferon alpha-2b works differently. It helps slow cancer cell growth, triggers cancer cell death and stimulates immune activity within the bladder to help eliminate bladder cancer cells. The in vitro results suggest that the tumour reduction and immune activation induced by light-activated Ruvidar may increase the sensitivity of residual tumour cells to interferon activity. This combined effect could potentially enhance treatment efficacy and extend the durability of response in patients with high-risk BCG-unresponsive NMIBC CIS. These findings support the scientific rationale for combining Ruvidar with interferon, which is planned in the company's coming combinational clinical study, which will enroll and treat patients diagnosed with Bacillus Calmette-Guerin unresponsive non-muscle invasive bladder cancer carcinoma in situ with or without resected papillary disease (plus or minus Ta/T1). Mark Roufaiel, PhD, research scientist at Theralase, commented: "These findings provide mechanistic support for our combinational clinical study. By inducing targeted tumour destruction and immune activation with light-activated Ruvidar, we hope to create a microenvironment more responsive to interferon alpha-2b. The enhanced total cell kill observed in vitro supports the potential of this complementary approach to improve outcomes for patients with BCG unresponsive NMIBC." Arkady Mandel, MD, PhD, DSc, chief scientific officer, Theralase, stated: "Our preclinical research demonstrates that light-activated Ruvidar combined with interferon may provide significant benefit to patients afflicted with high-risk BCG unresponsive NMIBC CIS, with or without papillary tumours. This combinational approach aligns with current thinking of combining world-class drugs to offer even higher efficacy, duration of response and safety for patients. I believe that the strong preclinical results demonstrated today will be confirmed clinically in the upcoming collaborative clinical study." Roger DuMoulin-White, BSc, PEng, ProDir, president, chief executive officer and chairman of the board of Theralase, added: "Our preclinical research has been used successfully to support design and development of our clinical programs. This has allowed our clinical programs to succeed, both in safety and efficacy, as they are firmly rooted in science. I look forward to reviewing the clinical data from the upcoming combinational clinical study." About Theralase Technologies Inc. Theralase is a clinical-stage pharmaceutical company dedicated to the research and development of energy-activated small molecules for the safe and effective destruction of cancer, bacteria and viruses. We seek Safe Harbor.