One of this week’s major end of the week movers is large-cap biotechnology company TESARO Inc (NASDAQ:TSRO). As many reading might already be aware, the company has long been pitched as a potential buyout candidate in the sector. A number of companies have been put forward as potential suitors but, as yet, none of the rumors have been confirmed and – with the latest update – it now looks as though any buyout is a lot further away than markets initially expected.

During the session on Thursday, a report from CNBC said the following:

“There is nothing imminent at all, the sources said. The expectation the company had in terms of price were not met by the incoming expressions of interest it got from potential bidders, according to the sources.”

The quote is based on information from an unnamed source, or sources, but one that is reportedly close to the company and has extensive knowledge of the ongoing situation.

Over the last couple months, Tesaro has picked up strength on rumors of a buyout, with the strength rooted in the fact that markets generally expect to see any potential suitor pay a premium to open market share price at acquisition time. As such, a large portion of the current share base is likely only in the company because of the buyout rumors as opposed to any pure fundamental expectations. When we see a report like this, one that essentially negates the rumors entirely, it results in a flight from the company of these positions and – by proxy – a down turn in its market capitalization.

We are seeing the real-life interpretation of this concept in Tesaro’s share price right now, with the company trading around 10% down on its preannouncement capitalization.

This might not seem like a considerable loss, but for a company of Tesaro’s size, it’s pretty substantial. If we were looking at a small biotechnology company, the equivalent decline would be somewhere in the region of 40 to 50%.

So, what’s next?

Well, chances are the decline will result in a relatively long-term revaluation based on the fact that the shares sold represent the portion of the market that were in Tesaro in anticipation of a buyout. If rumors once again start to pick up, and we get something a little more solid, we may see the gap close going forward.

The second mover on today’s list is another biotech giant, this time around, Mylan N.V. (NASDAQ:MYL). It is also much more traditional move. On Thursday, the company announced that an FDA advisory panel meeting had concluded, one put together to discuss the ongoing progress of its application for approval of a drug designed as a bio similar to Herceptin, which is Roche Holding Ltd. (ADR) (OTCMKTS:RHHBY)’s blockbuster oncology asset. It is primarily used as a breast cancer treatment right now and generates billions of dollars in revenues for Roche annually. During the first nine months of 2016 alone, the drug pulled in $5.1 billion for the company.

A number of companies have tried to produce biosimilars for this market in an attempt to try and redirect some of these revenues from Roche towards their own balance sheet. As yet, none have been particularly successful. Mylan, however, intends to buck this trend with its attempt.

So what happened with the panel?

Well, as per yesterday’s announced outcome, all members of the advisory panel voted in favor of approval for the drug, with a vote count of 16 to 0. While the FDA doesn’t have to follow the decision of its advisory panel, when the outcome is this clear cut, it would be a bit of a surprise if the agency chose to go against the recommendation. In short, this means that there is a good chance of the drug picking approval come decision day and – by proxy – it’s a strong step in the right direction for Mylan. Markets are recognizing this and buying up the company in response to the announcement.

The news came after hours so we are yet to see the full impact of the development. However, as things stand, Mylan is up around 2% on its pre-release capitalization. Chances are we will see this company run further throughout the session on Friday and heading into the weekend.