UPDATED: FDA experts endorse new COPD blockbuster from GlaxoSmithKline, Theravance

GlaxoSmithKline and Theravance have nailed down a solid majority of FDA panel votes in favor of marketing their new COPD combo therapy Anoro Ellipta. The outside experts voted 11 to 2 on Tuesday to endorse the therapy, opening the door to the first of several new drugs that will likely wind up duking it out in a tough fight for market share.

Anoro Ellipta emerged from a broad program initiated by GSK ($GSK) and South San Francisco-based Theravance ($THRX). Analysts have provided some good odds that the LAMA/LABA combo can break through the $1 billion blockbuster barrier, provided the agency follows up with an approval later this year.

The odds are good that it will. An internal FDA review offered support for the lower of two doses being offered by the development team. It's quite common for the agency to err on the side of safety when it comes to dosages, and regulators went to the panel to get feedback on just that lower dose. The partners appear eager to get started marketing at either dose.

The solid vote in the developers' favor came despite some clear unease among several of the panelists about the therapy's safety profile, which prompted a call for post-marketing studies to clarify the risks involved. Those safety concerns could also dog the product once it's cleared for marketing.

Rivals also won't be far behind.

Boehringer Ingelheim offered up Phase III data over the weekend for olodaterol at the annual meeting of the European Respiratory Society. Boehringer is trying to protect the $4.7 billion franchise it has for Spiriva, which competes against GlaxoSmithKline's $8 billion Advair while AstraZeneca ($AZN) earns $3.2 billion from Symbicort. 

Novartis ($NVS) hopes to shake the market up with QVA149, another LAMA/LABA. The EMA endorsed the once-daily drug in July. But facing some challenges at the FDA, an NDA isn't expected in the U.S. until later in the year. In the meantime AstraZeneca acquired Pearl Therapeutics for up to $1.15 billion in June in a bid to control its own LAMA/LABA program. Forest Laboratories and Almirall also have a new COPD treatment in the pipeline.

Citigroup is estimating that the COPD market is likely to swell from $10 billion this year to $14 billion in 2018. But when you look at the swelling ranks of competitors, the math may not work well for the current market leaders like GlaxoSmithKline. Bloomberg reports an average projected peak sales estimate for their new therapy at $1.4 billion, blockbuster territory but still far short of what Advair brings in. And this week the FDA mapped a short path for developers interested in coming up with generic versions of that drug, which lost patent protection in 2010. 

GlaxoSmithKline, though, sees the glass as half full.

"Today's recommendation is good news and a reflection of our commitment to giving an alternative treatment option for patients living with COPD--a disease that affects millions of Americans," GlaxoSmithKline President of Pharmaceuticals R&D Patrick Vallance said in a statement. "If approved, Anoro Ellipta will be the first, once-daily dual bronchodilator available in the US, marking another significant milestone for GSK's portfolio of medicines to treat respiratory disease. We will continue to work with the FDA as they complete their review."

- here's the press release

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