We're living out the memorable opening line of Charles Dickens' classic novel A Tale of Two Cities. It really is both the best of times and the worst of times.

Identifying what makes this the worst of times is easy. The coronavirus pandemic has arguably caused the greatest disruption to everyday life since World War II. But for investors, the resulting stock market crash has presented one of the greatest buying opportunities for stocks in our lifetimes.

There are bargains to be found in pretty much every sector. Healthcare is no exception. Here are three healthcare stocks that are dirt cheap and appear to be great buys right now.

Doctor holding stethoscope up to healthcare-related icons.

Image source: Getty Images.

1. AbbVie

AbbVie (NYSE:ABBV) shares currently trade at less than 9 times expected earnings. That kind of low valuation might make sense for a company likely to experience an earnings decline, but that's not the case for AbbVie.

Granted, the big drugmaker faces some headwinds for its top-selling drug, Humira. Biosimilar rivals are already eating into the blockbuster drug's market share in Europe and will do the same in the U.S. beginning in 2023. However, AbbVie has been planning for this eventuality for years. I think the company's in good shape to survive and thrive in a post-Humira world.

AbbVie isn't as dependent on Humira as it used to be, thanks in large part to fast-rising sales for cancer drugs Imbruvica and Venclexta. Its pipeline has also been fruitful, with new immunology drugs Rinvoq and Skyrizi likely to rake in billions of dollars in sales annually over the next decade. And AbbVie's pending acquisition of Allergan will reduce its reliance on Humira even more.

Even with the challenges to Humira, Wall Street analysts expect AbbVie's earnings will increase by an average of close to 5% annually over the next five years. With the company's tremendous dividend yield of nearly 7% thrown into the mix, I think AbbVie will deliver attractive total returns for a long time to come.

2. Alexion Pharmaceuticals

If you like AbbVie's low valuation, you'll probably love Alexion Pharmaceuticals (NASDAQ:ALXN). This biotech stock trades at close to 7.5 times expected earnings. Factoring in Alexion's growth prospects makes its valuation look even more appealing.

Some might question just how much Alexion will be able to grow because of concerns about its flagship drug, Soliris. It's true that several key patents for Soliris will expire over the next few years. It's also true that a potential rival could soon be on the scene, with Apellis Pharmaceuticals reporting late-stage results earlier this year in which its drug pegcetacoplan produced greater improvement in hemoglobin levels of patients with rare blood disorder paroxysmal nocturnal hemoglobinuria (PNH) than Soliris did.

However, Alexion has its own successor to Soliris already on the market. That drug, Ultomiris, was even ranked as the top new drug launched last year by market researcher EvaluatePharma. So far, Ultomiris has been approved for treating PNH and atypical hemolytic uremic syndrome. Alexion is also evaluating the drug in treating other rare diseases, including generalized myasthenia gravis (gMG) and neuromyelitis optica spectrum disorder (NMOSD).

Alexion could even help in fighting coronavirus. The company is exploring the potential for Soliris in treating patients with severe cases of COVID-19 along with severe pneumonia or acute respiratory distress syndrome (ARDS). Alexion is already providing the drug as an experimental emergency treatment for some patients.

3. Bristol Myers Squibb

Bristol Myers Squibb (NYSE:BMY) is another cheap pharma stock, with shares trading at less than 9 times expected earnings. As was the case with Alexion, the company's tremendous longer-term growth prospects make BMS an even bigger bargain.

You only have to look at BMS' current product portfolio to see where a lot of that growth will come from. Two of the company's drugs, blood thinner Eliquis and cancer immunotherapy Opdivo, are on track to rank among the five best-selling drugs in the world, according to EvaluatePharma. Sales are also soaring for several of the company's other drugs, notably including multiple myeloma drugs Empliciti and Pomalyst.

What really makes Bristol Myers Squibb stand out, though, is its pipeline. The company has quite a few trials underway that could lead to additional approved indications for Opdivo, either as a monotherapy or in combination with Yervoy. It hopes to pick up additional approvals for other already-approved drugs as well, including Idhifa and Reblozyl. Most importantly, BMS anticipates launching several potential blockbusters by the end of 2021, with multiple sclerosis drug ozanimod heading up the list.

Then there's the dividend, which currently yields close to 3.7%. Anyone concerned that the acquisition of Celgene last year might impact BMS' dividend program can put those worries to rest. The drugmaker boosted its dividend by 9.8% in December. My take is that great growth prospects plus a great dividend make Bristol Myers Squibb a no-brainer stock to buy right now.