Idenix Pharmaceuticals Inc. took advantage of the tailwind in its stock, which on Tuesday hit a 52-week high of $7.38, by pricing a public offering disclosed one day earlier.

The underwritten registered public offering of 9.4 million shares at $6.50 per share would raise $61.1 million, with the potential for another $9.2 million through the underwriter's option to purchase up to 1.4 million shares for overallotments. The offering represents only a 9.1 percent discount over Tuesday's close at $7.15.

The shares will be issued in conjunction with a $150 million shelf registration statement filed last month with the SEC that reported 96.2 million shares outstanding as of Sept. 30.

J.P. Morgan Securities LLC is acting as sole book-running manager and underwriter for the offering, which is expected to close Nov. 21.

Shares (NASDAQ:IDIX) of the Cambridge, Mass., firm closed Wednesday at $6.99, down 16 cents.

The new offering represents the second financing this year for Idenix, which last traded at more than $7 in September 2008. In April, when shares were trading below $4, Idenix raised $58.9 million by offering twice as many shares – 18.3 million – priced at just $2.80. (See BioWorld Today, Apr. 11, 2011.)

Earlier this month, Idenix reported third quarter revenues of $2.6 million, compared to $3.8 million in the third quarter of 2010, and a third quarter net loss of $11.7 million, compared to a net loss of $12.9 million in the same period a year earlier.

Total revenues for the nine months ending Sept. 30 were $7.7 million, compared to $7.8 million for the first nine months of 2010, with a net loss of $33.9 million for the nine months ending Sept. 30, compared to a net loss of $45.4 million for the same period a year earlier. Idenix said the $11 .5 million reduction in its 2011 net loss was due primarily to lower expenses in its protease inhibitor and non-nucleoside polymerase inhibitor programs, lower salaries and personnel-related costs and lower costs related to the timing of clinical trials of IDX184. Partially offsetting those reductions was an increase in expenses related to preclinical development of the company's NS5A drug candidates.

Idenix also reported cash and equivalents of $64.7 million as of Sept. 30 and anticipated royalty payments associated with product sales of Tyzeka/Sebivo (telbivudine), for hepatitis B, would provide sufficient capital at least to the second quarter of 2012.

Telbivudine was co-developed by partner and majority shareholder Novartis AG, of Basel, Switzerland, which holds exclusive worldwide commercialization rights. (See BioWorld Today, March 27, 2003.)

Through a spokesman, Idenix declined to comment on the financing. But David Standring, the company's chief scientific officer, said last week at the Credit Suisse Healthcare Conference that royalties from the Novartis deal would help move the oral nucleotide polymerase inhibitor IDX184 for hepatitis C virus (HCV) across the finish line. IDX184, whose progress has risen and fallen like a roller coaster and remains under a partial clinical hold, will report interim results from a Phase IIb study early next year on the first 30 patients to complete one month of therapy. (See BioWorld Today, Feb. 11, 2011.)

'We hope these data will confirm the efficacy and safety of IDX184 and will provide the basis for the release of the partial clinical hold,' he said.

Preclinical data have demonstrated broad antiviral activity, and the compound has the potential to become a backbone nuc in the evolving HCV treatment regimen, Standring added, noting that Idenix expects 'multiple value inflection points' from IDX184 in the near future, based on clinical milestones and partnering opportunities.

Idenix also is developing non-nucleotide inhibitor IDX375, NS5A inhibitor IDX719 and additional nucleotide inhibitors for HCV, and it expects to file an investigational new drug application for IDX719 by year-end, according to Standring. Although Idenix has two HCV protease inhibitors in preclinical development, the company has suspended work on those programs for the time being.

Idenix also outlicensed the NNRTI GSK2248761 (formerly IDX899), for HIV, to GlaxoSmithKline plc, of London, in February 2009, but that compound received an FDA clinical hold in February. (See BioWorld Today, Feb. 9, 2009, and Feb. 11, 2011.)

Pending the FDA's release of the partial clinical hold, Idenix has multiple options for IDX184, including advancing the drug in house or with a collaborator or outlicensing the compound. Early results of IDX184 suggested the compound is safe and demonstrated potency at least on par with competing candidates. But the bar for nucleotide inhibitors in HCV was raised considerably following the stunning findings on interferon-free regimens that Pharmasset Inc. reported at American Association for the Study of Liver Disease in San Francisco. (See BioWorld Today, Nov. 8, 2011.)

In an update following Idenix' third quarter earnings report, Credit Suisse biotechnology analyst Adam Cutler asked a question that company officials must have pondered as well: How does IDX184 catch up to the rapidly advancing HCV field? Although nucs are scarce assets, 'IDIX shares are unlikely to go up significantly until 184 demonstrates its value in an interferon-free regimen,' Cutler wrote.

Standring agreed that the HCV landscape is shifting like desert sands, noting that 'by far the most attractive option at this point' is to study IDX184 without interferon.

'It is quite clear that the race to eliminate interferon is already on at this point,' he said. With a core competency in nucs and flush with another $70 million, Idenix could put the pedal to the metal.

In other financing news:

• Adventrx Pharmaceuticals Inc., of San Diego, closed its public offering of 21 .25 million shares of its common stock and warrants exercisable for up to 10.6 million additional shares for gross proceeds of about $17 million. The securities were sold in a fixed combination of one share and a warrant to purchase 0.5 of a share at a price to the public of 80 cents per unit. The warrants have an exercise price of $1.10 per share and a five-year term. The company said net proceeds are approximately $15.7 million after underwriting discounts, commissions and estimated offering expenses are deducted. Proceeds will be used to fund continued development of its lead product candidates and for general corporate purposes. Since getting a complete response letter for lung cancer drug Exelbine (vinorelbine injectable emulsion) earlier this year, Adventrx said it plans to seek a partner for that drug candidate and focus its resources on ANX-188 (purified poloxomer 188), a treatment for pediatric patients with sickle cell disease in acute crisis, and ANX-514 (docetaxel for injectable emulsion) for breast cancer. Rodman & Renshaw LLC acted as sole book-running manager for the offering. Shares of Adventrx (AMEX:ANX) fell 3 cents, to close at 62 cents on Wednesday. (See BioWorld Today, Aug. 11, 2011.)

• Athersys Inc., of Cleveland, entered an equity purchase agreement with Aspire Capital Fund LLC, which committed to purchase up to $20 million of Athersys' common stock in multiple transactions over the next two years at a modest discount to the prevailing market price. At closing, Aspire Capital purchased 666,667 shares of common stock at $1.50 per share, adding to its existing holdings in the company that it acquired in a February financing. Athersys will control the timing and amount of any common stock sales to Aspire and will know the sales price before giving notice to Aspire to purchase shares. The companies placed no limitations on the use of proceeds, future financings or rights of first refusal.

• Pacira Pharmaceuticals Inc., of Parsippany, N.J., priced its public offering of 7 million shares of common stock at $6.50 per share, with expected net proceeds of approximately $42.3 million. The company granted underwriters a 30-day option to purchase up to an additional 1.1 million shares for overallotments, which could generate an additional $6.8 million. Barclays Capital Inc. and Jefferies & Co. Inc. are acting as joint book-running managers for the offering, with Piper Jaffray & Co., Wedbush PacGrow Life Sciences and Brean Murray and Carret & Co. acting as co-managers. Pacira's shares (NASDAQ:PCRX) closed Wednesday at $7.38, up 50 cents.