Arena’s cannabinoid pain drug passes early-stage test


After a fairly traumatic 12 months, Arena Pharmaceuticals ($ARNA) will be looking to ease its own agonies and focus on its research after posting positive Phase I data for its cannabinoid 2 receptor pain drug.

The placebo-controlled Phase 1b clinical trial looked at 36 healthy adults to evaluate the safety of multiple-ascending doses of APD371 and showed only low-level AEs, meaning it can now pass into the next stage of testing.

The most common adverse events were headaches and nausea, with all AEs classified as mild, according to a statement from the San Diego, CA-based biotech.

Drug levels at all doses tested in the trial, including the lowest dose, were also well above those believed to be needed to stimulate the CB2 receptor, according to the company. Preclinical data has shown some effect on osteoarthritic and neuropathic pain.

William Shanahan Jr., Arena’s senior VP and chief medical officer, said: “The results of this trial substantiate data from our single-ascending dose trial of APD371. In both trials, we achieved dose-responsive exposure without dose-limiting adverse events across the range studied.”

This will be some much needed good news after a torrid few quarters for the company. In the fall of 2015, Arena kicked its CEO and co-founder Jack Lief out of the company and followed this up with a move to ax 35% of its staff--some 80 jobs--while narrowing its R&D focus.

More cuts are also expected as Arena deals with losing market share with its obesity drug Belviq, which has proved to be a troublesome therapy to market. It said it was focusing on more near-term projects--although APD371 has a good few years ahead of it.

APD371 works as an orally available agonist of the CB2 receptor PD371 and is designed to provide pain relief without the psychotropic effects typically seen with marijuana--although its link to marijuana is fairly low as it has much less activity on the CB1 receptor, the stimulation of which can cause many adverse effects and undesirable behaviors.

Arena hopes that targeting the CB2 receptor will in fact avoid or reduce the potential for the dependence or abuse associated with opioid drugs--something that could make its life much easier if it gets to the regulatory approval stage and help it shake off the link to marijuana.

APD371 could be Arena's foothold into a highly-lucrative industry as an estimated 100 million American adults suffer chronic pain--and the global pain management therapeutics market was estimated to be worth $29 billion in 2010.

London’s GW Pharmaceuticals ($GWPH) is one of the bigger players when it comes cannabinoid CBD therapies, with its Sativex approved for the treatment of spasticity due to multiple sclerosis (and also undergoing trials for cancer pain) and its experimental Epidiolex, a liquid formulation of cannabidiol, in late-stage testing for epilepsy.

There are also a number of other companies that have used cannabinoid properties to make anti-nausea drugs for cancer patients, with others also on the market for specific areas of pain, such as neuropathic and chronic pain. Medical marijuana is also now approved in 24 U.S. states.

-check out the release