Moberg Pharma AB has announced that interim data from a subset of patients in its ongoing North American Phase 3 trial of MOB-015 for onychomycosis (nail fungus) revealed lower than anticipated clinical cure rates. This development casts uncertainty on the drug's potential for US market approval. The study, which involves 384 patients across 33 sites in the US and Canada, is pivotal for securing registration and commercialization of MOB-015 in the United States.
The current Phase 3 trial differs from previous studies that supported marketing authorization in 13 EU countries. The North American trial uses a reduced dosage regimen consisting of 8 weeks of daily dosing followed by 40 weeks of weekly maintenance treatment, compared to daily dosing throughout the entire treatment period in prior trials.
Clinical Cure Assessment
Clinical cure is one of three parameters required to achieve the study's primary endpoint of complete cure. All three parameters—clinical cure, negative fungal culture, and negative microscopy—must be met for a patient to be considered completely cured. The recent data pertains only to clinical cure, with no information available yet on the other parameters.
The data is blinded, meaning that the company does not know which patients received MOB-015 and which received the vehicle (placebo). Patients were randomized 2:1 to receive either MOB-015 or the vehicle.
Impact and Next Steps
According to Moberg Pharma, the lower-than-expected clinical cure rates in this subset of patients have significantly increased the risk of not being able to commercialize the product in the US based on the current study. The company is prioritizing the integrity of the study data to maintain the possibility of using the results in discussions with regulatory authorities.
"Our main priority is to protect the data integrity of the study," said Anna Ljung, CEO of Moberg Pharma. "Together with our CRO, we will do our utmost to minimize the time from the last patient's last visit to top-line data, and our expectation is that these may be brought forward compared to the timelines previously communicated, before year-end."
Moberg Pharma has stated it will refrain from speculating on potential outcomes or the future potential of MOB-015 until topline results are available.
About MOB-015 and Onychomycosis
Onychomycosis affects approximately 10% of the general population, with a significant portion remaining untreated. MOB-015 is a topical formulation of terbinafine designed to deliver effective concentrations of the drug to the nail and nail bed while minimizing systemic exposure. Oral terbinafine, while considered the gold standard, carries risks of drug interactions and liver damage. MOB-015 has already received marketing authorization in 13 countries based on previous Phase 3 trials that demonstrated superior mycological cure rates (76% vs. up to 42% for comparators) and better complete cure rates compared to the vehicle, without serious adverse reactions. The ongoing North American Phase 3 study evaluates patients over 52 weeks, with the primary endpoint being the proportion of subjects achieving complete cure of their target nail.
