US-based pharmaceutical company Xeris Biopharma has dosed the first participant in a Phase II clinical trial of subcutaneous (SC) XP-8121 injection to treat adults with hypothyroidism.
The trial will assess the tolerability and safety of XP-8121 (levothyroxine sodium) in patients with hypothyroidism, who will be subcutaneously injected with the therapy once a week.
It will also determine a target dose conversion factor from stably dosed oral levothyroxine to XP-8121.
The study is being carried out as a self-controlled, non-randomised, multi-centre, single-arm, open-label trial.
It will include a titration period of two to eight weeks, screening and a four-week maintenance period.
During the maintenance period, a subset of patients will undergo a pharmacokinetic sub-study.
Xeris global development and medical affairs senior vice-president Kenneth Johnson said: “We are excited to have dosed the first participant in our Phase II dose-finding study of XP-8121 and are actively recruiting additional participants that meet the eligibility criteria.
“We anticipate a lengthy recruitment period as enrolling stably dosed patients with normal TSH on oral levothyroxine is challenging and speaks further to the need of developing a once-weekly SC injection.
“Depending upon enrollment rates, we anticipate completing the study in the first half of 2024.”
Safety data and the derived average once-weekly dose of XP-8121 from this study will allow Xeris to begin a Phase III programme.
Xeris chairman and CEO Paul Edick said: “Oral levothyroxine is one of the most prescribed medicines in the United States, generating more than 100 million prescriptions a year.
“We believe that our novel SC formulation of levothyroxine has the potential to provide patients with a once-weekly dosing, thereby potentially improving treatment adherence, as well as bypassing the gastrointestinal (GI) tract.”
Xeris is also engaged in developing formulations for treating endogenous Cushing’s syndrome, primary periodic paralysis and severe hypoglycaemia.