SAN FRANCISCO – What a fantastic week for the biotech industry. As the doors closed on the 32nd Annual J. P. Morgan Healthcare Conference last week, delegates will surely have left with the lasting impression, if they hadn’t formed it before, that the sector is alive and well and poised for another great year.

Perhaps the most overused phrase by executives of the presenting companies was “excited for their future.” That outpouring of confidence was justified by the fact that many of those firms are riding a period of accommodating capital markets, which has prevailed for more than 12 months, and companies are enjoying positive sales growth if they have products on the market and are developing strong and deep pipelines with many products in late-stage clinical trials.

This enthusiasm has certainly rubbed off on investors. To gauge just how much the environment impacted stock values, BioWorld Insight calculated the percentage gains or losses of the 76 biotech companies who gave presentations during the conference. For the four-day period ending Thursday, Jan. 16, that group performed very well, increasing by an average of almost 6 percent. In contrast, the general markets were flat during the same period; the Dow Jones Industrial average remained virtually unchanged and the Nasdaq Composite Index closed up 1 percent.

Top gainer in the group was Sarepta Therapeutics Inc., of Cambridge, Mass., with a 44 percent jump in its stock price. In addition to its corporate presentation, the company released data through week 120 from Study 202, a Phase IIb open-label extension study of eteplirsen in patients with Duchenne muscular dystrophy (DMD). Results through more than two years showed a continued stabilization of walking ability in eteplirsen-treated patients evaluable on the six-minute walk test. The company previously reported that Study 202 met its primary endpoint of increased novel dystrophin as assessed by muscle biopsy at week 48 and is now in the long-term extension phase in which patients continue to be followed for safety and clinical outcomes.

Also among the top gainers was another Cambridge, Mass.-based company, Alnylam Pharmaceuticals Inc., with its stock value increasing 33 percent, driven by the disclosure that Sanofi SA unit Genzyme, also of Cambridge, had bought $700 million worth of its shares at $80 each, a 27 percent premium to the average share price over the last month. (See BioWorld Today, Jan. 14, 2014.)

The headline-making development gave Genzyme about a 12 percent stake and made the company a major shareholder in Alnylam with significantly broader rights to its collaborator’s lineup of RNAi candidates.

Alnylam also revealed that it was buying Merck & Co. Inc.’s subsidiary, Sirna Therapeutics Inc., for $25 million in cash and $150 million in stock, with the promise of as much as $115 million in milestone payments and royalties to Merck, of Whitehouse Station, N.J., which bought Sirna for $1.1 billion in 2006 but has done little with the assets. (See BioWorld Today, Nov. 1, 2006.)

Although the stock surge of both Sarepta and Alnylam was driven by news events, Agios Pharmaceuticals Inc., whose stock increased 45 percent, and PTC Therapeutics Inc., with a stock price increase of 36 percent, did not issue any news.

Interestingly, Celgene Corp., which delivered JPM’s inaugural presentation, was one of the few companies in the group that saw its shares close down by 1.3 percent. That came despite the fact that it reported that it was raising its 2015 earnings per share guidance from a range of $8 to $9 to a range of $9 to 9.50 and its 2015 revenue guidance from a range of $8 billion to $9 billion to a range of $8.5 billion to $9.5 billion, with longer term 2017 guidance boosted, as well.

The industry’s top biotech by market cap, Gilead Sciences Inc., saw its share price close up 4 percent, and Amgen Inc. recorded a very modest 0.88 percent gain.

Overall, the industry is off on the right foot.