Theravance (THRX) began a phase II “proof of concept” clinical trial for one of its pipeline candidates, TD-1211. The drug, an orally-administered peripherally selective mu opioid receptor antagonist (PUMA), is being studied to evaluate its effectiveness, tolerability and safety in patients with opioid-induced constipation (OIC).
Results from studies of TD-1211 on healthy volunteers have shown that the drug was well tolerated at all doses administered. The phase II study is looking to evaluate the constipation-relieving effects, safety and tolerability of the drug in patients who have been experiencing constipation during a chronic opioid therapy.
The trial, to be conducted on 50 patients, will be randomized so that patients receive either TD-1211 (orally once daily dosage) or placebo along with their opioid treatment for over 14 days. The primary endpoint of the study is the frequency of spontaneous bowel movements (SBMs). The frequency of SBMs in patients receiving TD-1211 compared to placebo will be evaluated in the study.
We believe there is an unmet medical need in this area as no drugs are currently approved in the US to treat constipation resulting from the chronic use of opioids. Results from the trial are expected later this year.
Although the initiation of the phase II trial is a positive development for the company, we believe the biggest potential in the pipeline is the Relovair Program, in collaboration with GlaxoSmithKline (GSK). The collaboration is looking to develop products to treat asthma and chronic obstructive pulmonary diseases (COPD).
The Relovair program aims to replace one of Glaxo’s best selling drugs Advair, which recorded global sales of $8 billion in 2009. The drug is slated to lose patent exclusivity in 2010 in the US and in 2013 in Europe.
Development of the pipeline is quite crucial for Theravance as it has only one marketed product, Vibativ for the treatment of complicated skin and skin structure infections (cSSSI) caused by Gram-positive bacteria, including resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA).