Momentum is building for biopharmaceutical mid-cap InterMune (NASDAQ:ITMN), which reported strong year-over-year sales gains in the first quarter for lead drug Esbriet, a treatment for idiopathic pulmonary fibrosis.

For the quarter, InterMune reported a 188% year-over-year increase in Esbriet sales, to $30.3 million from $10.5 million in the year-ago period. Furthermore, this was an 18% sequential increase from the $25.7 million in revenue recorded in the fourth quarter, as InterMune notes that its IPF therapy is now launched and reimbursable in 14 of its 15 top-priority European markets.

Investors need to know that InterMune is planning to resubmit its application for pirfenidone, the scientific name for Esbriet, with the Food and Drug Administration in the U.S. early in the third-quarter. With its new drug application being a class 2 resubmission, it anticipates a review process of just six months. If all goes well, InterMune anticipates a drug launch in the U.S. during the second quarter.

Research and development expenses rose 24% during the quarter, to $32.1 million, reflecting the higher costs associated with its ASCEND phase 3 trial and activities related to its preparation for a new drug application in the U.S. Selling, general, and administrative expenses also jumped 48%, to $44.3 million, which InterMune primarily attributed to pre-launch preparations in the U.S.

Net loss for the quarter widened 7%, to $53.6 million, from the year-prior period, but fell on an EPS basis due to more shares outstanding, to $0.59 from $0.64 in Q1 2013.

Looking ahead, InterMune boosted its full-year revenue forecast for Esbriet to a range of $130 million to $140 million, an 85%-100% increase from the $70.3 million in reported sales in 2013. InterMune kept its R&D and SG&A forecasts unchanged at $110 million-$120 million and $210 million-$225 million, respectively.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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