Daiichi Sankyo, said to have spurned an AstraZeneca bid, says it's 'not the fact'

Daiichi Sankyo
Daiichi Sankyo bears a market value of about $16 billion and could bring some attractive antibody medications to the table.

Did Daiichi Sankyo receive a buyout bid from AstraZeneca last year? According to the Japanese drugmaker, no.

In response to a story from Japanese publication Nikkei Business, which claimed Daiichi had turned away an AZ acquisition bid, Daiichi released a short statement on Thursday saying, "this is not the fact." It's still unclear, however, whether the two companies discussed a deal more informally.

No clarification was forthcoming from AstraZeneca. "We have nothing to share as we don’t comment on rumors or speculation," a spokeswoman said via email.

Before Daiichi's rebuttal, Nikkei's report sent shares skyward by as much as 13% and triggered a trading halt on the Nikkei exchange.

RELATED: Daiichi Sankyo to beef up ADC production with $135M investment in Japan

If AZ and Daiichi did talk takeover, it may have been Daiichi’s expertise in antibody drug conjugates that drew the pharma giant, Nikkei noted. These so-called “armed antibodies” link monoclonal antibodies to cell-killing agents and bear better disease-targeting capabilities. And the company earlier this year said it would plow ¥15 billion—about $135 million—into its domestic manufacturing ops to produce the medications.

Daiichi’s work in the space has sparked the interest of fellow immuno-oncology drugmaker Bristol-Myers Squibb, for one; the New Jersey company earlier this week inked a pact to test its Opdivo treatment alongside Daiichi’s DS-8201 in some breast and bladder cancers.

RELATED: AstraZeneca's Mystic shortfall is an immuno-oncology shake-up for Bristol-Myers and a bolster for Merck and Roche

A Daiichi buy could have helped AstraZeneca toward its lofty $45 billion revenue goal for 2023; the U.K. company has pegged cancer medications to make up a large part of that total. Those ambitions recently took a hit when a combination of I-O drug Imfinzi and candidate tremelimumab failed to outperform chemo or solo Imfinzi in a key lung cancer trial.

Daiichi wouldn’t have come cheap, though. It boasts a market value of about $16 billion, Reuters noted.

AZ and Daiichi, meanwhile, already have a longstanding relationship that includes a marketing tie-up over constipation drug Movantik in the U.S. and a 2010 deal on Nexium in Japan.