It's no secret that the global population has grown significantly older over the past few decades. In fact, the global median age has steadily risen every decade from 21.5 years in 1970 to 30.9 last year due to a combination of declining birth rates and improved longevity. And with the global median age projected to rise to 38.7 by 2070, this trend is one that isn't going away anytime soon.

This raises the following question: How can investors take advantage of this unstoppable demographic trend? Since an aging population will likely require more prescription drugs, I believe that these three dividend-paying biotech stocks are great picks for investors to buy right now.

A doctor and patient talk to each other during an appointment.

Image source: Getty Images.

1. Viatris

With the global prescription drug industry expected to grow from $1.03 trillion this year to $1.41 trillion by 2026, it will become increasingly important for patients, doctors, and insurers around the world to control prescription drug spending. An increased emphasis on generic and biosimilar drugs to keep costs down should bode well for biotech stock Viatris (NASDAQ:VTRS).

While 39% of its $13.5 billion in year-to-date revenue was already derived from generic and biosimilar drugs, this share will grow even more in the years ahead for two reasons. Firstly, Viatris' branded drugs (such as Viagra, Lipitor, and EpiPen) will likely experience continued revenue declines as they have already been off patent for a period of time. Secondly, the company is preparing a number of generic and biosimilar drug launches.

One recently approved biosimilar drug that will launch soon and be a major contributor to Viatris' future revenue growth is Semglee, which is the direct alternative to Sanofi's blockbuster insulin drug Lantus. Semglee, which Viatris owns with Indian drugmaker Biocon Biologics, was recently the first insulin biosimilar to be added to Express Scripts' National Preferred Formulary -- a list of insured medications -- which will allow even more patients access to the drug.

Viatris' biosimilars for blockbuster drugs such as Eylea (used to treat diabetic retinopathy and wet age-related macular degeneration) and Avastin (used to treat various cancers) have been submitted to regulatory agencies and could soon receive approval.

The biggest selling point for Viatris besides its solid pipeline and promising prospects for generics and biosimilars is its absurdly cheap valuation. Viatris' forward price-to-earnings ratio of less than four and 3% dividend yield makes it a no-brainer biotech stock buy for patient income investors. 

2. Pfizer

Investors should also consider buying Pfizer (NYSE:PFE). Lately, this mega cap pharma stock is most famous for the COVID-19 vaccine that it co-developed with BioNTech (NASDAQ:BNTX), known as Comirnaty, which it estimates will make up 44.2% of its $81.5 billion in forecast revenue this year.

Yet Pfizer remains far more than its COVID vaccine. The company boasted 7% year-over-year growth from its portfolio of non-Comirnaty products in the third quarter, led by anticoagulant drug Eliquis and rare heart disease drugs Vyndaqel and Vyndamax, which points to a strong portfolio overall.

Second, Pfizer's oral pill used to treat COVID-19, known as Paxlovid, stopped clinical trials early due to its successful results; it reduced the risk of hospitalization or death among patients at risk of developing severe disease by 89%. This will almost certainly give Pfizer a blockbuster therapy upon receiving Emergency Use Authorization (EUA) from the U.S. Food and Drug Administration (FDA), which could be just months away.

At $48 a share, Pfizer is priced at less than 12 times this year's estimated adjusted earnings per share (EPS) -- and while investors wait for the stock to be awarded a higher valuation multiple to reflect its culture of innovation, they can collect an enticing 3.2% dividend yield that is well-covered by its business.

3. Bristol Myers Squibb

Nearly 40% of American men and women will be diagnosed with cancer at some point during their lifetime, according to the National Cancer Institute. The good news is that cancer treatments are continuing to improve and one of the companies responsible for major scientific advancements in the treatment of cancer is Bristol Myers Squibb (NYSE:BMY).

Revlimid and Opdivo are two of Bristol Myers' three top-selling drugs that are used to treat patients with various forms of cancer, which comprised 43.7% of the company's $34.4 billion in total year-to-date revenue.

While Revlimid, Opdivo, and Eliquis -- an anticoagulant blockbuster shared with Pfizer -- are all set to lose their exclusivity this decade, Bristol Myers has the necessary pipeline to eventually move past these drugs. That's because the company has more than 50 compounds in various stages of development.

Bristol Myers trades at just eight times this year's adjusted EPS forecast while yielding a market-beating 3.3%. That, along with the company's strong pipeline, makes the stock one you can consider buying and holding a long time.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.