Spero Therapeutics announces preliminary findings from Phase 1 trial of SPR206
Spero Therapeutics announced preliminary findings from its Phase 1 first-in-humans clinical trial of SPR206, an IV-administered product candidate being developed by Spero as an innovative option to treat MDR Gram-negative bacterial infections. Analysis of preliminary, blinded data from the Phase 1 double-blind, placebo-controlled single ascending dose and multiple ascending dose clinical trial in healthy adult volunteers suggests that SPR206 is well-tolerated at doses that are likely to be within a therapeutic range for target MDR Gram-negative bacterial infections and has a safety profile that Spero believes supports the further development of SPR206. The decision to continue development of SPR206 is also supported by data from nonclinical studies in which SPR206 demonstrated activity as a single agent against MDR and extensively drug resistant bacterial strains, including isolates of Pseudomonas aeruginosa, Acinetobacter baumannii and carbapenem-resistant Enterobacteriaceae, in both in vitro and in vivo models of infection.The Phase 1 clinical trial of SPR206 evaluated the safety, tolerability and pharmacokinetics of intravenously administered SPR206 at single doses ranging from 10 mg to 400 mg in seven SAD cohorts and repeat total daily doses ranging from 75 mg to 450 mg for seven consecutive days and 300 mg for 14 consecutive days across five MAD cohorts. A total of 96 healthy volunteers were randomized to receive SPR206 or placebo. All reported adverse events were mild to moderate and there were no reported severe or serious adverse events. No evidence of nephrotoxicity was observed and there were no subjects with clinically significant changes in laboratory tests during the study. Although the data remain blinded, an analysis of preliminary data indicates that SPR206 was well-tolerated at doses up to 100 mg administered three-times a day, a total of 300 mg daily, for 14 consecutive days. Preliminary analyses of pharmacokinetic data across the cohorts indicates dose linearity and dose proportionality as well as mean plasma drug exposures of SPR206 that are concordant with preclinical models predictive for clinical efficacy against target Gram-negative pathogens. Spero expects to receive a development milestone payment from its partner Everest Medicines upon delivery of the SPR206-101 SAD/MAD clinical study report as specified under the regional collaboration launched in 2019 and expects to present final data from the Phase 1 clinical trial in the first half of 2020. In conjunction with Everest Medicines, and through its grant from the U.S. Department of Defense awarded in July 2019, Spero plans to conduct a Phase 1 bronchoalveolar lavage clinical trial assessing the penetration of SPR206 into the pulmonary compartment in the second half of 2020 as well as initiate a renal impairment study of SPR206.