New acne drug formulation offers improved tolerability

Key Points

Fort Worth, Texas - Recently approved Atralin (tretinoin gel 0.05 percent, Coria Laboratories) performs comparably to tretinoin alternatives, while offering better tolerability, an expert says.

"Atralin is a new retinoid formulation that is as effective as some of the established ones, such as tretinoin 0.1 percent gel, but less irritating," says Guy F. Webster, M.D., clinical professor of dermatology, Jefferson Medical College, Philadelphia, and founder and immediate past president, American Acne & Rosacea Society (AARS).

In one of the drug's phase 3 studies, Atralin showed efficacy comparable to that of Retin-A Micro (tretinoin 0.1 percent, Ortho Neutrogena), with greater tolerability.

"The credit for that greater tolerability goes to a well-constructed vehicle," which includes hyaluronic acid, collagen and glycerin, Dr. Webster says.

"This formulation decreases irritation and helps the skin repair itself," he says.

The study

The 12-week, multi-site, blinded, randomized study included a total of 936 patients with mild to moderate facial acne vulgaris, who got either tretinoin gel 0.05 percent (375 subjects), tretinoin gel 0.1 percent (376 subjects) or Atralin's vehicle alone (185 subjects).

Subjects applied the assigned preparation nightly for 12 weeks, with investigator evaluations occurring at baseline, then at weeks one, two, four, eight and 12.

Investigators eliminated from their analysis subjects who under- or overapplied their preparations by 20 percent either way, Dr. Webster says.

At week 12, tretinoin gel 0.1 percent achieved a 58.8 percent median reduction in inflammatory lesion counts versus a 48.1 percent median reduction for tretinoin gel 0.05 percent. Median noninflammatory lesion counts decreased by 58.3 percent and 50 percent, respectively, while median reduction in total lesion counts showed an 11.7 percent advantage for tretinoin gel 0.1 percent.

However, "The incidence of treatment-related adverse events was highest in the Retin-A Micro group," with 65 percent of these patients reporting adverse events that investigators judged to be related to treatment, says Mark Smith, Coria Laboratories product director.

The corresponding figure among the tretinoin gel 0.05 percent cohort was 53 percent.

Results and conclusions

Overall, Dr. Webster says that compared to patients in the tretinoin gel 0.1 percent group, those in the tretinoin gel 0.05 percent group experienced a quarter as much scaling, one-third as much erythema and half as much dry skin.

"That's a significant improvement over the comparator," he says.

A second phase 3 study compared tretinoin gel 0.05 percent (299 subjects) versus the product's vehicle alone (302 subjects), using the same 12-week protocol.

Patients in the former group achieved mean reductions in inflammatory and noninflammatory lesion counts of 27.9 percent and 36 percent, respectively.

The corresponding figures in the vehicle-treated group were 15.4 percent and 19.3 percent, Mr. Smith says.

As for adverse events, 46 percent of patients in the tretinoin gel 0.05 percent group experienced treatment-related adverse events, versus 24 percent of placebo-treated patients.

"These were standard topical retinoid studies required by the FDA, so there's at least some basis for comparison to other data that's out there," Dr. Webster says.

"It's hard to see any drawbacks with the product. It's not like this is a new active agent - vitamin A has been around for decades for treating acne,"and physicians know its capabilities, Dr. Webster says.

FDA approved Atralin for acne vulgaris on July 27, 2007.

Disclosure: Dr. Webster is a consultant to Coria.

For more information: http://www.jefferson.edu/
AARS: hbaldwin@downstate.edu