Sirnaomics Ltd. (the "Company", Stock Code: 2257.HK, together with its subsidiaries, the "Group" or "Sirnaomics"), a leading biopharmaceutical company in discovery and development of RNAi therapeutics, reported that a poster with positive clinical data of STP705 for focal fat reduction (FFR) was presented at the 2023 Fall Clinical Dermatology Conference, which took place October 22–25 in Las Vegas. The safety and efficacy results of this Phase I study support further investigation of STP705 as a potential alternative to other injectables for FFR.

The poster, titled "Phase I Study to Evaluate the Safety and Tolerability of Subcutaneous Injection of STP705 in Adult Subjects Undergoing Abdominoplasty," was presented by Dr. Mark S. Nestor's team from Center for Clinical and Cosmetic Research, Aventura Florida. The presentation provided a summary of the Phase I study, which aimed to explore the safety and tolerability of STP705 in patients undergoing abdominoplasty, while making initial observations on the efficacy of STP705 to induce adipocyte apoptosis for fat reduction.

"The results of our Phase I readout for STP705 using an RNAi injectable drug for focal fat reduction are encouraging," said Dr. Patrick Lu, Ph.D., Founder, Chairman of the Board, Executive Director, President and Chief Executive Officer of Sirnaomics. "The low incidence of local skin reactions and the histology observations showing adipocyte destruction and fat remodeling provide robust evidence that STP705 may become a best-in-class drug candidate for focal fat reduction and is worth further investigation."

Results include:

• STP705 was well-tolerated at all doses, concentrations, and volumes.
• STP705 demonstrated an excellent safety with very few local skin reactions (LSRs).
• There were very few observed treatment-associated adverse reactions and these resolved without intervention.
• STP705 may have a favorable safety profile when administered locally for the purpose of fat reduction.
• Histologic analysis performed on excised tissue samples provided further evidence of STP705's activity in adipocyte destruction, which occurred in a suggested dose-response manner; this will guide future clinical dosing parameters for optimal efficacy and safety.

The study protocol consisted of 3 treatment cycles administered 28 days apart. Each treatment cycle calls for 7 subcutaneous injections consisting of either 120 μg, 240 μg, or 360 μg of STP705 in 0.5 and 1.0 ml doses (per injection) and 1.0 ml of placebo. Patients were randomized in a double-blind manner and injected in seven 1 cm² areas across the lower abdomen. Eight subjects aged 18–65 received injections with follow-ups occurring at 2 and 7 days post procedure.

Tissue samples from each of the 7 injection sites were harvested from the total abdominoplasty excisional specimens obtained 28 days after the final round of injections. Safety assessments were conducted throughout the study, including evaluation of LSRs, and collection of any adverse events. Lipolytic and inflammatory effects of STP705 were assessed by blinded histologic analysis of harvested tissue samples, and each of the samples was given a histology score corresponding to the degree of the observed inflammatory response.

"The results for this clinical study are very encouraging for the potential use of STP705 for localized fat reduction," said Dr. Michael Molyneaux, M.D., Executive Director and Chief Medical Officer of Sirnaomics. "We continue to see excellent safety with this asset and the results we see in patients in this study are very consistent with what we have seen in our non-clinical work in fat reduction. There remains a high unmet need for noninvasive treatment modalities and as the demand for medical aesthetics continues to grow, the product has the potential to fit very well with the current trends towards noninvasive aesthetic medicine."

"The poster presented at the Fall Clinical Dermatology Conference shows data culminating from the Phase I study. As both a researcher and a clinical dermatologist, I'm extremely excited about both the safety and efficacy of STP705 for fat reduction and remodeling," said Dr. Mark S. Nestor, M.D., Ph.D., Voluntary Professor, Department of Dermatology and Cutaneous Surgery, Department of Surgery, Division of Plastic Surgery, University of Miami, Miller School of Medicine. "I am most excited about the extremely low incidence of localized skin reactions, which is the main concern for the current injectable fat reduction drug on the market."