|
Urinary incontinence (UI) involves the involuntary leakage of urine, which can be leakage accompanied by or immediately preceded by urgency (urge UI), leakage on exertion (stress UI) or a combination of both (mixed UI). Although treatment rates are traditionally low due to a decreased awareness of the disease and a hesitance amongst patients to approach physicians, UI is a well established condition and there have been drugs available to treat it for about two decades.
The current leading class of drugs are the anticholinergics, taken in a pill form. There are currently four once-a day anticholinergics on the market; Detrol (tolterodine), Ditropan (oxybutynin), Vesicare (solifenacin) and Enablex (darifenacin), with two more, Sanctura XR (trospium chloride) and Toviaz (fesoterodine), set to come onto the market in the next couple of years.
There are several unmet needs in the UI market which the current anticholinergics do not satisfy. The current treatments demonstrate a high incidence of side effects associated with the cholinergic system, including the undesirable dry mouth, and patients often try several different treatments before finding one that works. Despite these drawbacks, a lack of alternatives has ensured that this has remained the dominant class for the treatment of urge UI.
There is however, a lack of available treatments for stress UI, with Europe having only the antidepressant Yentreve (duloxetine) on the market, and no treatment at all approved in the US. There is a need for alternative targets and mechanisms of action to deliver an improved efficacy profile.
Novel anticholinergic reformulations demonstrate promise
Novel reformulations of the current anticholinergics have demonstrated some promise in the treatment of urge UI in reducing the anticholinergic side effects. A topical patch, Oxytrol, containing a traditional anticholinergic drug, oxybutynin, produced by Watson was thought to be able to revolutionize the UI market, bypassing the gastro-intestinal (GI) tract and thus the cholinergically observed side effects. Unfortunately due to side effects experienced with the patch itself, such as skin irritation and the fact that the patch was not potent enough - in some cases requiring the user to wear several patches - the patch never really took off.
However, in a promising move for UI sufferers, Watson and Antares are currently developing a topical gel formulation of oxybutynin that will have all the benefits of the anticholinergic treatments without the unwanted anticholinergic side effects. Watson has announced positive Phase III data from its oxybutynin gel and is expected to launch its gel in early 2009. Meanwhile, Antares' oxybutynin gel is currently in Phase III trials. With a fast track program, Antares expects to have its product on the market six months after Watson's. The gel will come as a welcome relief to many patients experiencing the anticholinergic side effects, in particular elderly patients who already have to deal with a high pill burden.
The gel treatment is forecast to prosper by offering patients an alternative to the current oral treatments, and thus succeeding in a niche market. Datamonitor forecasts sales will reach over $200 million.
While drug delivery reformulations offer a mid-term opportunity in the UI market, for a truly commercially successful long-term approach, and for a significantly improved benefit to the patient, a novel mechanism of therapeutic action is required. Examples of the possible mechanisms of action beyond the anticholinergics can be observed in the development pipeline, which include the NK-1 antagonists and the adrenergic modulators.
SUI is a great unmet need
There is still a great unmet need in the stress UI market. While drugs are available to treat urge UI, there are no licensed treatments in the US and only the antidepressant, Yentreve (duloxetine) in Europe to treat stress UI. The untapped stress urinary incontinence (SUI) market in the US is an area of great unmet medical need, with a potential 28 million SUI patients in the US alone. A drug that is FDA approved for SUI would be a welcome relief to many SUI sufferers and would benefit from first to market status in the US.
Currently, SUI is treated with the use of pads or surgical intervention. There is, as such, great potential for a pharmaceutical company to move into this market and market a drug for SUI in the US. The promising mechanisms of action in the current SUI pipeline include drugs which act on the adrenergic and NK-1 mechanisms. Several treatments in early Phase II are currently being developed for the potential treatment of SUI and Datamonitor believes current players would be well served to invest in this niche patient group.
Related research
|
