Eli Lilly’s recent submission of a supplemental New Drug application to US regulators for the antidepressant Cymbalta has highlighted a market that could grow in value from under $400 million in 2006 to $2 billion by 2016, according to a new study.

Consultancy firm Datamonitor says that fibromyalgia, a “relatively common yet poorly understood syndrome” which affects six million people in the USA alone (mainly middle-aged women) and is characterised by widespread muscle pain and fatigue, costs the latter’s economy around $13 billion each year. It has “historically been substantially underserved by both the medical profession and the pharmaceutical industry,” but this began to change when Pfizer received US marketing approval in June for its epilepsy and neuropathic pain drug Lyrica (pregabalin) to treat fibromyalgia.

Datamonitor estimates that Lyrica fibromyalgia sales will grow to $641 million in 2016, but there are currently some 20 drugs in development that could challenge Pfizer’s top spot. That number is expected to grow over “as the predicted success of new drugs such as Lyrica, as well as a better defined regulatory pathway and patient population encourages other companies to consider investment”, the report claims.

Lilly’s Cymbalta could be approved for fibromyalgia by 2008 and Datamonitor CNS lead analyst Ben Greener thinks that with additional Phase III trials being conducted, Forest/Cypress’s milnacipran will be the third drug approved by the FDA for this indication. Several other candidates in late stage development offer further promise for fibromyalgia patients, including sodium oxybate, lacosamide, rotigotine, reboxetine, and radafaxine, he added.

“Of the mechanisms of therapeutic action targeted by pipeline companies, agents altering levels of dopamine are particularly promising,” Mr Greener said, “with a growing amount of literature suggesting a link between this neurotransmitter and fibromyalgia pathology.” Two such agents are UCB’s rotigotine and GlaxoSmithKline’s radafaxine.

The report goes on to note that an accurate diagnosis of fibromyalgia “is hindered by a lack of disease awareness and understanding among the general public and medical community” and primary care physicians require the most education about the condition. Mr Greener concluded by saying that “Pfizer and other drug companies will do well to conduct physician education programmes that improve understanding of diagnosis and treatment awareness”.