In most years, April isn't a special month to buy stocks. It's not a bad time to invest, but there's nothing that makes April better than other months. But this April is different. 

Because of the coronavirus pandemic and the subsequent stock market plunge, this month is a very good time to invest in stocks. I'd argue that it's an especially great time to invest in shares of big drugmakers. Many pharma stocks have been hammered much harder than is warranted. My view is that three pharma stocks stand out as the top picks to buy in April.

Multicolored pills forming a dollar sign

Image source: Getty Images.

1. AbbVie

There's one overwhelmingly compelling argument for buying shares of AbbVie (NYSE:ABBV). The drugmaker's dividend yields 6%. Investors who buy AbbVie now will lock in a juicy yield that should only get better in the future.

Including the time that it was part of Abbott Labs, AbbVie has paid out a dividend in every year since 1924. It's increased the dividend payout for a remarkable 47 consecutive years. And since being spun off from Abbott in 2013, AbbVie's dividend has nearly tripled.

Can AbbVie keep the dividends flowing and growing? I think so. Sales continue to soar for the company's cancer drugs Imbruvica and Venclexta. AbbVie's new immunology drugs Rinvoq and Skyrizi are expected to become megablockbusters over the next few years. The drugmaker's pending acquisition of Allergan will bring successful products including Botox and antipsychotic drug Vraylar into its lineup.

The primary headwind for AbbVie is the loss of exclusivity for its top-selling drug Humira in Europe, with the prospects of biosimilar competition in the U.S. only three years away. However, AbbVie should be able to offset the sales declines for Humira with its current products, promising pipeline candidates, and the addition of Allergan. The company might not deliver awe-inspiring earnings growth, but with its tremendous dividend, it doesn't need to in order for investors to still enjoy solid total returns.

2. Bristol Myers Squibb

If you're looking for great growth prospects in addition to a nice dividend, check out Bristol Myers Squibb (NYSE:BMY). The big drugmaker's dividend yield stands at more than 3%, which isn't too shabby at all. But I think that BMS is poised to generate impressive growth over the next few years.

It certainly helps that BMS claims two of the drugs that market researcher EvaluatePharma projects will rank in the top five best-selling blockbusters in the world by 2024 -- blood thinner Eliquis and cancer immunotherapy Opdivo. BMS also has a couple of rising stars with arthritis drug Orencia and multiple myeloma drug Empliciti.

But the acquisition of Celgene in November 2019 was a game changer for Bristol Myers Squibb. The company's lineup now includes blockbuster blood cancer drugs Revlimid and Pomalyst, along with solid tumor drug Abraxane. And thanks to the Celgene deal, BMS also now has recently approved drugs Reblozyl and Zeposia that have blockbuster-sales potential.

More winners should be on the way. Celgene's pipeline was loaded with great candidates that BMS now has. The most promising of these include cell therapies ide-cel and liso-cel. Wall Street analysts project that BMS will grow its earnings by an average of more than 18% annually over the next five years. With this kind of growth plus its attractive valuation and strong dividend, Bristol Myers Squibb appears to be a no-brainer big pharma stock to buy in April.

3. Pfizer

Pfizer (NYSE:PFE) is a good pick to buy right now for investors who want to get ahead of what's on the way. I'm referring to Pfizer's plan to spin off its Upjohn unit and merge it with Mylan (NASDAQ:MYL) to form a new company that will be named Viatris. Although the COVID-19 pandemic has caused Pfizer to delay the transaction, it's still set to wrap up later this year.

My view is that Pfizer will be set to deliver growth that's better than most big pharma companies once the Upjohn-Mylan deal finalizes. The "new" Pfizer" will have a strong lineup including breast cancer drug Ibrance, Eliquis (which it co-markets with Bristol Myers Squibb), prostate cancer drug Xtandi, and rare-disease drug Vyndaquel. 

The company's pipeline also includes eight programs awaiting regulatory approvals and over 20 programs in late-stage clinical studies. I'm especially optimistic about the prospects for pneumococcal vaccine PF-06482077.

Pfizer's dividend currently yields close to 4.4%. Although the dividend will be reduced after the Upjohn-Mylan transaction is completed, the combination of the dividend that Viatris is expected to pay out and the "new" Pfizer's dividend should be close to the level of Pfizer's current dividend.