US firm SCOLR Pharma has dropped development plans for a controlled release phenylephrine (PE) formulation, in light of slow progress in the over-the-counter (OTC) PE market.
SCOLR was developing a 12-hour controlled release phenylephrine formulation using the company's proprietary controlled delivery technology (CDT), but last week announced that the extended release treatment "did not justify continued internal development."
As a result of new laws that came into force in the US in September last year, many US-based pharmaceutical companies have been looking to PE as an alternative to pseudoephedrine (PSE) for use in their nasal decongestion products.
US regulators, concerned about the growing incidence of PSE-based products being diverted to illegally produce the street drug methamphetamine, restricted the sale of drugs containing the decongestant. All products containing PSE now have to be kept behind the counter, no more than 3.6 grams a day of such drugs can be sold to individual customers, and they must present photo identification and sign a log-book on purchase.
In order to bypass these requirements, many drug companies started investigating the possibility of reformulating their pseudoephedrine-containing drugs with phenylephrine, suggesting that the market for OTC PE products would be set to grow at a rapid rate.
However, compared to PSE, PE has some distinct disadvantages which have hampered the development of PE-based products and slowed the anticipated growth of the market. Phenylephrine does not last as long as pseudoephedrine, making it a less attractive choice for consumers, and there have also been concerns regarding its efficacy with some parties claiming it is little more effective than a placebo.
The combined annual market for decongestants is around $1bn (€0.8bn) in the US alone, and SCOLR was not alone in seeing an opportunity to develop phenylephrine formulations that could open up a slice of this market to them.
"Unfortunately, or fortunately, depending on your perspective, the PE-based reformulations have not yielded a successful, cost-effective alternative to extended release PSE-based products nor have the new immediate release PE-based products become popular as replacements for PSE, a drug that appears to be more efficacious in a solid oral dosage form," Stephen Turner, SCOLR vice president and chief technology officer, told In-PharmaTechnologist.com.
"Therefore, the US OTC market for PE-based is still evolving but not to the extent originally anticipated"
As such, the company decided to drop its PE product development plans and reallocate its resources to programmes with greater market potential.
"Due to the numerous drugs in our development portfolio, we do not feel that any one programme has a significant impact on our business," Turner continued. However, the company believes that their CDT technology could yield a 12-hour PE release product with additional development investment, and could quickly reactivate the development programme "should business conditions warrant doing so…or should a partner decide to licence and fund further activities."
Although SCOLR has dropped development of its PE drug, the company has a PSE based decongestant product that is doing well. The firm expects to make a US abbreviated new drug application (ANDA) submission for a CDT-based 12-hour PSE tablet later this year.
The product would compete directly with Pfizer's 12-hour Sudafed (pseudoephedrine hydrochloride) product, and the company has completed clinical studies establishing its products' bioequivalence with the Pfizer drug. In addition to this, SCOLR highlights the fact that its product is one third the size of the Sudafed tablets, potentially making it more attractive to consumers.
The firm is currently completing the chemistry, manufacturing, and controls (CMC) section of the ANDA with an undisclosed contract manufacturer, and expects the product to hit the shelves in late 2008 or early 2009.