Clinical stage pharmaceutical development company Incannex Healthcare (ASX: IHL) has held a pre-investigational new drug application meeting with the US Food and Drug Administration (US FDA) to discuss the regulatory pathway for lead candidate IHL-675A as a multi-use medication for the treatment of lung inflammation, inflammatory bowel disease and rheumatoid arthritis.
The company will now start designing a phase 1 clinical trial needed to assess these conditions in-humans with the aim of forming part of three investigational new drug (IND) applications for IHL-675A and associated studies required for the drug’s registration and marketing.
Indications prioritised for clinical assessment are acute respiratory distress syndrome (ARDS) and sepsis associated ARDS (SAARDS); pulmonary neutrophilia (the primary underlying cause of chronic obstructive pulmonary disease (COPD), asthma, and bronchitis); inflammatory bowel disease; and rheumatoid arthritis.
Incannex will combine development activities for ARDS, SAARDS and pulmonary neutrophilia into a common project known as the lung inflammation program.
These pulmonary conditions will be subject to one IND submission and will markedly increase the patient cohort required for future trials to include those with bronchitis, asthma, COPD, SAARDS, ARDS and COVID-related ARDS.
The other two development programs and INDs will be for inflammatory bowel disease and rheumatoid arthritis. Incannex says the three development pathways have increased the scope and economic potential of the drug.
Emergency Use Authorisation
The expanded lung inflammation development program contrasts with Incannex’s former plan to pursue an Emergency Use Authorisation (EUA) new drug application for just those ARDS patients with COVID-19.
EUAs are conditional on a continued state of emergency and subject to revocation by the US FDA once the emergency subsides.
The company noted it did not wish to limit its development program to COVID-19 ARDS patients.
“The success of [COVID] vaccines as a preventative measure has shortened the expected time in which therapies with EUA approval will persist without having to achieve full product registration,” it explained.
“An EUA application for COVID-19 ARDS remains accessible to [us] as a development option during the lung inflammation development program should the COVID-19 pandemic outlook worsen.”
Safety and efficacy reports
The US FDA also agreed marketing submissions for IHL-675A should include the 505(b)(2) New Drug Application (NDA).
An NDA contains full safety and effectiveness reports, but allows some of the information required for NDA approval, such as safety and efficacy information on the active ingredients, to originate from historical studies not conducted by Incannex.
“This will result in an accelerated and less-costly route to approval, compared with a traditional development path [505(b)(1)], whilst creating new and differentiated commercial products, subject to clinical success,” Incannex stated.
The US FDA panel also provided valuable guidance on the design of clinical trials, including opinions on the selection of clinical trial endpoints.
Incannex has received positive pre-clinical results from five in vivo assessments of IHL-675A to date, as it applies to various disorders caused by excessive inflammation.
“The combined annual global market size of the indications being targeted by Incannex with IHL-675A is over US$125 billion so we consider the economic potential, as well as the benefit to patients over incumbent treatments, to be enormous,” Incannex chief executive officer and managing director Joel Latham noted.