Singapore,  August 06,  2010: Generic erosion is set to shrink the allergic rhinitis market, said Datamonitor, which predicts a 20% decline in sales value over the next 10 years despite a marginal increase in sales volume.

Datamonitor estimates that there are approximately 181m people living with allergic rhinitis in the seven major markets, driving disease specific drug sales of approximately $5 billion in 2009. This is set to drop to $4 billion in 2019 as a result of the entrance of cheap generics following patent expiries, most notably in the US.

Despite the forecast drop in sales in the allergic rhinitis market, Datamonitor has identified potential growth areas, most notably in the immunotherapy segment of the market. Furthermore, life cycle management strategies have been identified that may help to lessen the impact of patent expiry of symptomatic treatments.

Jacoba van der Gaag, healthcare analyst at Datamonitor, said “Immunotherapy is the only treatment option for allergic rhinitis with a disease modifying potential, but concerns over cost and safety, particularly for subcutaneous formulations, have kept symptomatic treatments as the more popular choice. However, in recent years we’ve been witnessing large-scale development programs in immunotherapy for the first time, driven largely by new guidelines and changing regulations. This will always be a niche market, though this innovation is now promising growth.”

Datamonitor forecasts that two new sublingual tablets targeting grass allergies, Grazax (ALK-Abelló) and Oralair (Stallergènes), will have combined sales of $264m in the US and EU by 2019. The potential for growth in this market is reflected by the pipeline for allergic rhinitis, which is dominated by immunotherapies targeting multiple types of allergen.

Another opportunity exists within the antihistamine class, where life cycle management strategies are used to lessen the impact of generic erosion. An established strategy amongst key brands is the reformulation of molecules and/or combinations with decongestants. This strategy helps to reduce the loss to franchise sales and strengthen brand recognition following patent expiry of the primary molecule.

 Jacoba said, “The success of this strategy relies heavily on timing of new launches relative to generic entry. Merck’s Clarinex (desloratadine) suffered as a result of launching after its predecessor Claritin’s (loratadine) patent expired, which was demonstrated by it reaching only a quarter of Claritin’s peak sales in 2009. Meda Pharma, on the other hand, has seen successful patient switching from once to twice-daily azelastine having launched prior to patent expiry, and is developing an azelastine/fluticasone combination that is expected to further strengthen its franchise.”