On 25 May, Boehringer Ingelheim announced that its BI 425809 product had been granted Breakthrough Therapy Designation (BTD) by the US Food and Drug Administration (FDA) for cognitive impairment associated with schizophrenia (CIAS).
The schizophrenia market is dominated by established atypical antipsychotic treatments that manage the positive symptoms of the disorder. There are currently no approved pharmacological agents to treat the cognitive impairments seen in schizophrenia patients. If BI 425809 receives regulatory approval, it has the potential to address cognitive impairment in the market.
The BTD was supported by data from a 12-week, double-blind, randomised, placebo-controlled Phase II clinical trial in patients ages 18–50 years with schizophrenia. In the study, investigators found a greater mean improvement from baseline in cognitive function using the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery and Schizophrenia Cognition Rating Scale (SCoRS) scores after 12 weeks of once-daily treatment.
In addition, BI 425809 was well tolerated and adverse events were balanced across the treatment and placebo groups. As such, the key primary and secondary endpoints of the study were achieved. Boehringer hopes to replicate these positive results in the CONNEX trial program, which will consist of three Phase III clinical trials: CONNEX-1 (NCT04846868), CONNEX-2 (NCT04846881) and CONNEX-3 (NCT04860830). All three Phase III trials have estimated primary completion dates in May 2024. GlobalData forecasts that BI 425809 will launch in 2026 in the US.
Pfizer’s PF-03463275 is currently in Phase II development and is likely to compete with BI 425809. Both drug candidates can be orally administered and have a similar mechanism of action, targeting the sodium and chloride-dependent glycine transporter 1 (GlyT1). Since glycine acts as a co-agonist at the N-methyl-D-aspartate receptor (NMDA), blockade of the GlyT1 transporter is hypothesised to enhance NMDA receptor-mediated glutamatergic neurotransmission and, consequently, improve cognitive function.
A previous Phase II clinical trial for Pfizer’s PF-03463275 as an add-on therapy in patients with negative symptoms of schizophrenia was terminated due to low efficacy. It is currently, however, in ongoing Phase II trials to determine its efficacy in enhancing cognitive function in patients with schizophrenia or schizoaffective disorder, with an estimated primary completion date this December.
As BI 425809 is the only CIAS pipeline drug in Phase III development that has received BTD, it has the potential to become the first pharmacological treatment for CIAS. As such, GlobalData expects BI 425809 to have a first-to-market advantage over PF-03463275 for improving cognitive function in patients with schizophrenia.