Symbiomix Therapeutics LLC, which saw its single asset, Solosec (secnidazole, previously SYM-1219), approved by the FDA last month to treat bacterial vaginosis (BV), agreed to a buyout by Lupin Inc., the U.S. subsidiary of Mumbai-based Lupin Ltd., for $150 million, including $50 million up front. Lupin, which has a global presence but focuses largely on generics, earlier this year took an option to acquire privately held Symbiomix, which specialized in therapies to treat gynecologic infections.

"We wanted to get over the FDA approval of this," Vinita Gupta, Lupin Ltd.'s CEO and executive director, said on a conference call with analysts Wednesday. "We also wanted to see the label. We're very happy with the label and, therefore, [exercised] the option. We believe this is an anchor. It's a material milestone for us in our specialty evolution. And we are committed to building our specialty business as well as our women's health business over the next few years to offset some of the challenges that we see on the generic side of the business."

Solosec, a 5-nitroimidazole antibiotic with pharmacokinetics that enable delivery in a single dose, was approved as 2-g oral granules based on a development program that included two pivotal trials and an open-label safety study. The product becomes the first single-dose oral treatment approved to treat BV, which Lupin called the most prevalent gynecologic infection in the U.S. Compliance with current standard-of-care therapy is estimated to be approximately 50 percent, according to Paul McGarty, president of Lupin Pharmaceuticals Inc., who added that more than half of women treated for BV have a recurrence within a year.

During its development, Solosec obtained fast track and qualified infectious disease product (QIDP) designations from the FDA. The QIDP moniker makes Solosec eligible for at least 10 years of exclusivity in the U.S., giving Lupin "a very good run there to really build our women's health business" and "a strong fit strategically with our specialty business," Gupta said.

Solosec is expected to be available commercially by mid-2018.

"[Symbiomix] was in the process of validating the product from a manufacturing standpoint," Gupta explained, with the company's five-person team working primarily through third parties. Although "we would have loved to have the product ready to launch right now," he added, "we're going to complete the validation [and] get the launch quantities together that we need for the first year. We certainly want to be confident that we have the right quantities together to be able to service the share that we will target."

Waiting until mid-2018 also will give Lupin more time to work with payers to place the product on formularies to provide better access for patients and to add to its dedicated sales force so "there are no hurdles along the way," Gupta added.

He declined to offer guidance on pricing but cited a range of "$150 to $250 per treatment per prescription" for currently branded products in the U.S. BV market.

Seeking to 'make a difference' in women's health

Solosec is expected to expand Lupin's branded women's health specialty business, presently anchored by Methergine (methylergonovine), a semisynthetic ergot alkaloid used to prevent and control postpartum hemorrhage.

"We're having to build the commercial infrastructure," Gupta acknowledged. "We're starting with Methergine and now expanding it on Solosec. We'll want to build that in women's health, so we'll look to acquire or partner to develop other products that the market needs, [where] we can make a difference from a physician/patient standpoint."

Lupin also has been advancing its biosimilars franchise, moving in August to file for approval of its first candidate, an etanercept copy, in Japan and Europe. The asset was developed by Lupin's biotech research group in Pune, India, and licensed to YL Biologics Ltd., a startup partnered with Yoshindo Inc., of Toyama, Japan. (See BioWorld Today, April 28, 2014, and Aug. 10, 2017.)

Launched in 2012, Newark, N.J.-based Symbiomix sped quickly from baby steps to a full sprint to advance secnidazole in BV. In 2015, the company closed the third and final tranche of a $41 million series A, with participation from Orbimed Advisors LLC, Fidelity Biosciences, HBM Partners and Square 1 Bank. The financing was designed to move SYM-1219 through the phase III study and filing of a new drug application (NDA).

At the time, Symbiomix already had conducted an end-of-phase II meeting with the FDA, which agreed to review data from the phase II as one of two pivotal studies in the NDA filing. (See BioWorld Today, May 6, 2015.)

Symbiomix added $6 million last year, according to an SEC filing.

In addition to $50 million in cash at closing, which occurred Wednesday, and $100 million in payments over a seven-year period, Lupin agreed to make sales-based contingent payments. The acquisition was funded from Lupin's internal resources.

ICICI Securities Ltd. analyst Sriraam Rathi was bullish on the deal, writing in an update on Lupin that the acquisition "would help in expanding [the] specialty/branded portfolio of Lupin and would ramp up revenue contribution from specialty business to total revenue, which is less vulnerable to competitive and pricing pressure." Management expects a payback period of five to six years, he added, maintaining a buy rating on the company's shares (NSE:LUPIN), which fell INR17.75 (US$0.27) Wednesday to close at INR1,044.25 (US$16.02).