Exclusive: Cancer drugmaker Tesaro attracts takeover interest - sources

(Reuters) - U.S. biopharmaceutical company Tesaro Inc TSRO.O is discussing its options with investment banks after receiving acquisition interest from several drugmakers, according to people familiar with the matter.

A doctor exams mammograms, a special type of X-ray of the breasts, which is used to detect tumours as part of a regular cancer prevention medical check-up at a clinic in Nice, south eastern France January 4, 2008. REUTERS/Eric Gaillard

The takeover interest in Tesaro underscores the pharmaceutical industry’s strong appetite for the acquisition of biotechnology companies with promising medicines under development in lucrative sectors such as cancer treatment.

Tesaro is not actively exploring a sale, the people said this week, noting that there is a significant gap over the company’s valuation between Tesaro and potential acquirers.

However, the Waltham, Massachussets-based company is speaking to investment banks, including Citigroup Inc C.N, about its strategy and how to best respond to such overtures, the people added.

Additional clinical trial data later this year on Tesaro’s key drug, Niraparib, which targets advanced solid tumors in ovarian and breast cancers, could help narrow the valuation gap, the people said.

The sources asked not to be identified because the deliberations are confidential.

Tesaro and Citigroup declined to comment.

Tesaro shares rose as much as 17 percent on the news and were up 11 percent at $180.50 in late morning trading in New York on Wednesday, giving the company a market capitalization of more than $9 billion. Tesaro went public in 2012 at $13.50 per share.

Tesaro has been touted for months by analysts and investors as a likely acquisition target, in light of big deals in the biotechnology sector, such as Pfizer Inc's PFE.N $14 billion acquisition of cancer drugmaker Medivation Inc last September, and Johnson & Johnson's JNJ.N $30 billion announced acquisition last month of rare disease drugmaker Actelion Ltd ATLN.S.

Tesaro has a coveted position as a leader in the so-called immuno-oncology sector, which harnesses the body’s own immune system to combat cancer cells.

Its drug Niraparib kills cancer cells by inhibiting the production of proteins called PARPs, which help repair damaged DNA strands, thereby hastening the death of some types of cancer cells.

Effective PARP inhibitors are particularly sought after by drugmakers because of their potential to be used in combination with other types of cancer treatments to create new breakthroughs in treatments.

Niraparib is closer than any other PARP inhibitor to receiving regulatory approval for ovarian cancer maintenance therapy. Analysts say its peak sales could exceed $3 billion.

Last year, the U.S. Food and Drug Administration agreed to “fast-track” its Niraparib review process, raising the likelihood it could hit the market by 2018.

That would give it a significant head start over its main rival, Clovis Oncology Inc CLVS.O, whose similar treatment is in late-stage trials.

Last year, Tesaro entered into a partnership with pharmaceutical company Merck & Co Inc MRK.N to study the effects of using Niraparib in combination with Keytruda, Merck's immuno-oncology treatment.

Reporting by Carl O’Donnell in New York; Editing by Jonathan Oatis