Major drug companies across the US are in process of reformulating their over-the-counter cold medications in time for a new law that comes in to effect later this year restricting the sale of drugs that contain pseudoephedrine.
In a move aimed at stamping out the escalating "backyard production" of the illegal street drug methamphetamine, or "crystal meth, the recently passed Combat Methamphetamine Epidemic Act will come into effect in over 37 US states on September 30 and will require all products that contain pseudoephedrine to be kept behind the counter.
Customers will be allowed to buy no more than 3.6 grams a day of products containing pseudoephedrine and will have to show photo identification and sign a logbook at the time of purchase. Some states will even require a prescription for such products.
The law is set to damage sales of pseudoephedrine-containing drugs and most drug companies have already begun reformulating these products with phenylephrine, which can't be used to make methamphetamine, in order to bypass the restrictions. However, phenylephrine doesn't last as long as pseudoephedrine, so some drug makers are still leaving certain products as they are.
Pfizer is reformulating most of its pseudoephedrine-containing products, such as Benadryl and has already introduced a new phenylephrine-containing version of Sudafed, however it will also keep making original Sudafed with pseudoephedrine, Pfizer spokeswoman Erica Johnson told In-Pharmatechnologist.com.
Johnson and Johnson have been busy reformulating its Tylenol range of products and Wyeth is doing the same with Robitussin, the two companies indicated.
As part of the reformulation process, drug companies will need to perform analytics, formulation design, develop manufacturing processes and gather clinical data in order to demonstrate the chemistry of the revamped drugs, as well as demonstrating that they work and are safe and effective, a US Food and Drug Administration spokesperson told In- PharmaTechnologist.com.
Apart from the obvious costs involved, the replacement of pseudoephedrine with phenylephrine shouldn't pose too much of a problem for the pharma firms from a pharmaceutics point of view, as phenylephrine is a well-known, stable molecule and the excipients are known, Andrew Muddle, CEO of UK formulation firm, Medpharm, told In-PharmaTechnologist.com.
"However, the challenge may be making sure that the final dosage form developed is acceptable for the intended final use of the product, as well as being acceptable in the clinic," he said.
"The whole process until a new formulation is ready for market can take in excess of two years."
Meanwhile, fine chemical companies that have traditionally supplied the big drug firms with pseudoephedrine will shift production to making phenylephrine to accommodate the changes.