Transdel’s Topical Pain Reliever Falls Short on One Goal, Hits Another

Xconomy San Diego — 

[Updated: 10/06/09, 10:55 am Pacific] San Diego’s Transdel Pharmaceuticals released a mixed bag of clinical trial results this morning. The company’s topical pain reliever fell short on one of its two primary goals in a 364-patient study, but was successful for about two-thirds of patients who followed the study rules.

Transdel (OTC BB: TDLP) reported this morning that its topical cream version of ketoprofen, a potent non-steroidal anti-inflammatory drug from the same class as ibuprofen, was statistically better than a placebo in relieving pain after three days among the 252 patients with soft tissue injuries (sore necks, ankles, elbows, etc.) who followed the study protocol. The drug failed to show such an advantage, however, when researchers factored in the rest of the patients, who didn’t apply the drug correctly, or who took other medications, such as recreational drugs, that weren’t allowed under the study’s rules.

Transdel CEO Juliet Singh told investors today on a conference call that the company plans to discuss the results with the agency to talk about the best way to bring the drug forward. Singh, who previously worked with regulators to win market approval for botulinum toxin (Botox), says the FDA has asked to see both analyses of patients who follow the study rules and the whole population. If Transdel can convince the FDA to approve its product for sale in the U.S., it will start tapping into a global market for pain relievers that was worth $19.1 billion in 2008, and is expected to grow to $32.8 billion by 2013, according to market research firm BCC Research.

[Updated next three paragraphs with comments from Singh.]

“We have a successful Phase III study,” Singh says. “The FDA will look at both analyses in this trial.” The agency, “is fully aware of the challenges,” with examing all patients who enroll in a pain study, Singh adds.

Acute pain studies like Transdel’s are difficult to run because patients don’t have a chronic illness like cancer or diabetes, and sometimes don’t show up for follow up visits or fully follow study directions, Singh says. She stressed that Transdel didn’t fish through the data retrospectively to look for who benefitted—a practice many companies use to try to show some benefit for their drug. Rather, Transdel had planned in advance to do the analysis on patients who followed the protocol, and it was one of the study’s primary goals from the start, she says.

Hitting that goal of showing effectiveness in patients who completed the study is “a great achievement,” Singh says. She added, “This is where other companies have failed.”

The Transdel drug, to be marketed as Ketotransdel, is made to seep through the skin near the area of the body that’s in pain, without being fully absorbed into the bloodstream. That’s thought to help it avoid the side effects, such as stomach bleeding, sometimes caused by oral medicines from the same class.

The Transdel cream appeared to have a similar safety and tolerability profile to a placebo cream, and it wasn’t associated with any problems in the stomach or the heart, Transdel said in a statement. Only “minimal” concentrations of the drug were found in the bloodstream of a subgroup of patients who underwent that analysis.

Transdel plans to save more of the details from the trial for presentation at an upcoming medical meeting, and for publication in peer-reviewed journals.