Concert Pharmaceuticals reports results from two Phase 1 CTP-692 studies
Concert Pharmaceuticals reported results from two studies in its Phase 1 program evaluating CTP-692, a deuterium-modified form of D-serine being developed as an adjunctive treatment for schizophrenia. The safety assessments in the single- and multiple-ascending dose trials in healthy volunteers showed that the drug was well tolerated over the dose ranges tested, which include the doses expected to be evaluated in Phase 2 testing. Key blood and urine markers of kidney function did not indicate any signs of renal impairment. These data are consistent with preclinical findings with CTP-692 indicating an improved renal safety profile compared to non-deuterated D-serine which is known to produce renal toxicity in rats. Despite evidence of benefit in multiple published clinical studies of non-deuterated D-serine in the treatment of schizophrenia, its use has been limited due to renal safety concerns. Furthermore, in contrast to non-deuterated D-serine, which has been reported to display highly variable pharmacokinetic behavior in humans, CTP-692 was found to have low inter-individual pharmacokinetic variability. The company expects data from the single-and multiple-ascending dose Phase 1 trials to be presented at a future scientific meeting. The Phase 1 program was designed to assess CTP-692's safety, tolerability and pharmacokinetic profile in healthy volunteers. The Phase 1 program includes three studies: a crossover comparison of CTP-692 versus D-serine, a single-ascending dose study that also assessed the effect of food on the pharmacokinetics of CTP-692 and a multiple-ascending dose trial assessing CTP-692 dosed orally over seven days. In the single- and multiple-ascending dose trials, CTP-692 was evaluated across doses ranging from 0.5 to 4 grams compared to placebo in a total of 72 volunteers. CTP-692 demonstrated a favorable safety, tolerability and pharmacokinetic profile with no serious adverse events reported. In a separate study in 11 healthy volunteers treated in a crossover design with both CTP-692 and D-serine, CTP-692 was found to have increased plasma exposure compared to D-serine.