The U.S. remains firmly in the grip of a progressive opioid crisis of addiction and overdose. In 2019 nearly
50,000 people died of an opioid overdose and an estimated 3 million people have Opioid Use Disorder
(OUD). Libero Pharma’s program to develop a naltrexone transdermal patch will address multiple HEAL
objectives by providing new prevention and treatment alternatives, optimizing current medication-assisted
therapy, and improving access to treatment.
The antagonist naltrexone is one of only three medications with proven benefit in OUD relapse prevention.
With poor tolerance and compliance in oral form, intramuscular (IM) naltrexone is the only viable antagonist
option in the OUD population. Despite being approved in 2010, it is prescribed to fewer than 30,000
patients in the U.S. annually. Patient uptake is limited by availability, mode of administration (nurse-
administered 4mL deep gluteal injection), cost, and low adherence. Libero has assembled a highly
experienced team to bring to market a novel naltrexone transdermal patch (NNTP), which shares the
benefits of IM naltrexone in that it is non-addictive and avoids first-pass metabolism and the resultant
intolerance. As well as an easy-to-use alternative in OUD relapse prevention, NNTP also offers an
accessible and undaunting option both for stable patients looking to take the final step away from chronic
agonist use, and off-drug patients struggling with cravings at risk of relapse. The NNTP would eliminate the
administrative burden, patient discomfort, and cost barriers that currently limit the use of IM naltrexone.
This presents a genuine opportunity for widespread NNTP use in primary care where a vast and growing
opioid-dependent population urgently requires care.
This programme has been informed by clear input from the FDA, both in terms of plasma naltrexone level
requirements and the required regulatory steps. Libero will pursue a 505(b)(2) pathway to bring NNTP to
market for OUD relapse prevention. The UG3 Phase will include IND-enabling activities to secure an FDA
issuance of an IND. The UH3 Phase will evaluate efficacy and safety of the NNTP in a multi-site, double-
blind, randomized controlled trial against the IM naltrexone comparator over 6 months.