Celgene (NASDAQ:CELG) has a new spring in its step. The biotech stock performed dismally beginning in late 2017 after a major pipeline setback followed by a botched regulatory filing. So far this year, though, Celgene is a big winner.

The difference stems from Bristol-Myers Squibb's (NYSE:BMY) announcement in early January that it plans to acquire Celgene. But with BMS ready to buy Celgene, is the stock still a buy for regular investors?

Red ribbon forming a question mark on top of U.S. cash

Image source: Getty Images.

A virtual no-brainer

Bristol-Myers Squibb offered to acquire Celgene in a deal that valued the biotech at $102.43 per share. Considering that that represents a premium of nearly 17% over Celgene's current share price, buying Celgene stock appears to be a virtual no-brainer if the BMS acquisition is finalized.

Actually, the deal is even more attractive for investors who buy Celgene now. Each Celgene shareholder will also receive one Contingent Value Right (CVR) for each share they own. This CVR entitles holders to get another one-time payment of $9 in cash if the Food and Drug Administration (FDA) approves ozanimod and liso-cel by Dec. 31, 2020 and bb2121 by March 31, 2021.

What are the chances that investors will profit from the CVR offer? Pretty good. Ozanimod appears likely to win FDA approval easily based on its efficacy and safety profile. Celgene expects to file for approval of liso-cel in the second half of 2019. The biotech thinks it will secure FDA approval of bb2121 in the second half of 2020.

There's one potential negative that investors should know about, though. Bristol-Myers Squibb's offer would give each Celgene shareholder $50 in cash and one share of BMS stock. BMS' share price was $52.43 when the big pharma company first announced its potential acquisition of Celgene. The share price is a little lower now. Unless BMS stock bounces back before the closing of the transaction, the overall gain for Celgene shareholders from the acquisition will be reduced.

But what if the deal falls through?

Also keep in mind that it's possible that Bristol-Myers Squibb won't acquire Celgene. How could that happen? There are four potential scenarios that could scuttle the deal.

One is that regulators decide to put the brakes on Bristol-Myers Squibb's acquisition of Celgene. This is probably the least likely outcome, however. 

Another possibility is that another company steps in to buy Celgene at a higher price. This doesn't seem very likely, either. Even if it did happen, it would be good news for Celgene shareholders.

It's also possible that Celgene shareholders vote against the BMS acquisition. Why would they be against the deal? There's a pretty good argument to be made that Celgene is worth more than what BMS has offered.

Just a little over a year ago, Celgene was scooping up its own stock at prices higher than the price level that BMS has proposed. The biotech's prospects haven't materially changed since then, which could lead shareholders to conclude that Celgene would be better off over the long run either going it alone or holding out for a better deal.

Finally, there's a chance that Bristol-Myers Squibb shareholders will nix the acquisition of Celgene. Some investors weren't happy with the decision to buy Celgene. BMS also now has an activist investor, Starboard Value, that might not be in favor of the acquisition.

Should the BMS acquisition fall through, Celgene's share price would likely nosedive in the short term. Over the long term, though, the company's powerhouse lineup of Revlimid, Pomalyst, Otezla, and Abraxane, combined with an exceptionally strong pipeline, should enable Celgene to move higher than its current levels. 

To buy or not to buy?

Is Celgene a buy? My answer is an unequivocal "yes."

I think the odds are stacked in favor of the BMS acquisition of Celgene finalizing later this year. That means current Celgene shareholders should be in for nice gains within a few months and perhaps even sooner. But the clock is ticking.

Keith Speights owns shares of Celgene. The Motley Fool owns shares of and recommends Celgene. The Motley Fool has a disclosure policy.