Schwarz Parkinson's patch ploughs on

Schwarz Pharma's foray into the central nervous system disorder market is beginning to pay serious dividends as the firm's ground-breaking transdermal patch for Parkinson's continues to prove a success story, now gaining approval in the US market.

The company's Neupro transdermal patch, which delivers a continuous flow of anti-Parkinson's drug rotigotine over a 24 hour period, has been approved by the US Food and Drug Administration (FDA) for the treatment of signs and symptoms of early-stage Parkinson's, with a supplemental new drug application for the advanced stage of the disease due to be filed later this year.

Rotigotine belongs to a class of drugs known as non-ergolinic dopamine agonists, the latest generation of dopamine agents. Dopamine acts as a messenger substance between the brain and nerve cells, but Parkinson's patients do not produce enough of the chemical, resulting in transmission problems between the brain and the body leading to muscular tremors, weakness and impaired mobility.

Rotigotine and other non-ergolinic agents mimic the action of dopamine, and as such reduce the symptoms of Parkinson's. Where Schwarz's product stands above the only other two non-ergolinic products currently available is in the fact that it is delivered transdermally, offering a wealth of advantages over rival products.

Mirapex (pramipexole) by Boehringer Ingelheim and Requip (ropinerole) from GlaxoSmithKline are the only other non-ergolinic products currently available to Parkinson's patients, and both are delivered orally at least three times a day.

Neupro, in contrast, is the first once-daily, continuous delivery transdermal product, and on launch in the EU last year seriously outstripped its two competitors and outperformed even Schwarz's estimates.

The transdermal product solves a number of problems associated with current Parkinson's treatments. The other products currently available in the class require several doses a day, whereas Neupro can simply be stuck on the skin and left to release a continuous flow of the drug.

A common problem with the multiple dose regime used with the orally delivered products is what is known as the 'roller coaster' effect - patients experiencing fluctuation in the level of the treatment as earlier doses begin to wear off or as the most recent dose kicks in. To try and combat this unpleasant experience, many patients cut their pills in half and take them even more frequently to try and iron out the variation during the day. To compound this problem, is the fact that patients are rarely able to take their treatment overnight without interrupting sleeping patterns, so often wake up stiff and suffering the full onslaught of Parkinson's symptoms.

The transdermal patch appears to solve just about all of these common issues, and has proved popular with patients.

"The continuous release patch the only transdermal product available in this class of drugs," Antje Witte of Schwarz Pharma told in-PharmaTechnologist.com.

"It's a once daily product that can work both day and night - it's almost as good as our healthy brains."

Although the patch has been available in Europe for both early-stage Parkinson's and in combination with levodopa for advanced Parkinson's, the US approval is currently for early stage only. Schwarz decided to push ahead with the early-stage product rather than waiting for approval for advanced Parkinson's in order to get the product onto the US market as soon as possible, said Witte.

The patch itself can be worn anywhere on the body adn is available in a range of strengths according to the patient's needs. A 2mg per 24 hour dose is the smallest patch at 10cm², 4mg/24 hours is 20cm², and 6mg/24 hours in a 30cm² patch. A higher dose of 8mg per 24 hours is also available in the EU through a 40cm² patch, but this larger size will not be available in the US.

The cost of the patch on a daily basis is essentially the same as the oral treatments available, and the patch product has an industry standard shelf life with boxes of 100 patches available (i.e. a three month supply).

Schwarz has hit a growing market with this easy-administration non-ergolinic drug product. The entire Parkinson's disease market is worth around $2.5 - 2.7bn (€1.8 - 2.0bn), but there has been growing emphasis on non-ergolinic drugs as the treatment of choice for new patients.

Levodopa, a cheap generic drug, currently accounts for around 25 per cent of all Parkinson's disease treatment, but this share is dropping due to alternative products becoming available and the inherent neurotoxicity of the drug. A further 25 per cent of the market is taken by older ergoline drugs, but these are also experiencing a drop in popularity.

"In contrast, these latest generation non-ergolinic agents currently have 25 per cent of the market, but are experiencing double-digit growth - they are the future of the market," said Witte.

In the first nine months the patch product was available in Europe, it generated €9.5m for the company through treatment for early-stage Parkinson's only. The first quarter of this year has shown the strength of the product, and following approval for late-stage Parkinson's in early February sales of the product for both indications has totalled €6.4m.

Once approval has been granted in the US for use of the patch for treatment of late-stage Parkinson's, Schwarz Pharma has estimated EU and US sales of the product for both indications to hit around $350m.

"Parkinson's is a very difficult disease," said Witte, "and it can be a very conservative and hesitant market." Despite this, with professional opinion leaning towards recommending non-ergolinic agents for newly diagnosed patients and the growing market share reflecting this opinion, Schwarz would seem to be in a prime position to reap the rewards of a product that offers such distinct administration advantages over its current competitors.