Achilles Therapeutics, a Syncona portfolio company, has announced that an Independent Data and Safety Monitoring Committee (IDSMC) has completed its first review of the ongoing, first-in-human Phase I/II CHIRON and THETIS trials and has recommended that both clinical trials continue as planned. Achilles Therapeutics is a clinical-stage biopharmaceutical company developing precision T cell therapies to treat solid tumors. Furthermore, Achilles Therapeutics has also announced that it expects to consider additional capital raising options this year, which could include an initial public offering in the United States. Syncona’s announcement makes it clear that the timing and the terms of any such offering have not yet been determined and are subject to market conditions and other factors. It also says that there is no assurance that any such additional capital raising will be completed.
About CHIRON and THETIS
The CHIRON study is an open-label, multi-center Phase I/II trial evaluating the safety, tolerability, and clinical activity of cNeT therapy as a single dose in adult patients with advanced metastatic NSCLC. The THETIS study is an open-label, multi-center Phase I/II trial evaluating the safety, tolerability, and clinical efficacy of cNeT therapy as a single dose in patients with recurrent or metastatic malignant melanoma as monotherapy and in combination with a PD-1 inhibitor.
About the review
The review looked at the first six patients dosed with the Company’s Clonal Neoantigen Targeting T cell therapy (cNeTs). It found that the overall tolerability profile was similar to that of standard tumor-infiltrating lymphocyte (TIL) products that have not been enriched for cNeT reactivities, with the lymphodepletion regimen accounting for most higher-grade adverse events. Additionally, initial data from the first six patients provide encouraging evidence of cNeT engraftment. Based on these observations, the Company plans to increase the administered cNeT doses in the next series of monotherapy patients.
Following the first disease evaluation by scan six-weeks post cNeT infusion, stable disease was observed in four out of the six patients and progressive disease in two. One patient had a reduction in the size of two of their four tumor lesions by approximately 55% and 90%. Engraftment data for our cNeTs are currently available from four patients, with evidence of engraftment in two. The highest engraftment was in the patient who received the highest cell dose.
Comments from Dr Iraj Ali, Chief Executive Officer of Achilles Therapeutics
“This independent safety review along with the initial data from our CHIRON and THETIS trials are promising and are based on patients that have been dosed with cNeTs at the lower end of our prospectively targeted therapeutic dose range,”
“We now plan to move to higher cNeT doses and also open a combination cohort in the THETIS trial evaluating the addition of nivolumab, a PD-1 inhibitor, following cNeT infusion, subject to further safety review.”
Comments from Dr Karl Peggs, Chief Medical Officer of Achilles Therapeutics
“As engraftment and expansion of tumor-reactive T cells post infusion have been correlated to clinical response in T cell therapies, seeing engraftment of cNeTs at these relatively low dose levels is encouraging,”
“Importantly, we are able to demonstrate cell engraftment, expansion, and persistence as a result of our ability to characterize our product at the level of individual cNeT reactivities, in addition to quantifying polyclonality of the infused cNeTs and of the engrafted cells.”