The bear market has weighed on stocks across industries this year. Even some of the world's strongest companies have seen their shares decline in the double digits. But two biotech companies have defied today's difficult market.

Biogen (BIIB -0.92%) and Vertex Pharmaceuticals (VRTX 0.35%) have both climbed in the double digits -- and for good reason. Both companies may be set to launch exciting new products in the not-too-distant future. Which one of these top stocks represents the better bear market buy right now? Motley Fool contributors Adria Cimino and Keith Speights offer some answers.

Biogen makes a turnaround

Adria Cimino (Biogen): This year started out rocky for Biogen. The company watched its big dreams for its Alzheimer's disease drug, Aduhelm, disappear. The controversial treatment never gained support in the medical community. Biogen ended up dismantling the Aduhelm commercial infrastructure.

At the same time, Biogen faced decreasing revenue due to an aging product portfolio. Its blockbuster multiple sclerosis drug Tecfidera now faces generic competition -- and revenue is on the decline. In the most recent quarter, Biogen's total product revenue slipped 11%.

Then came the turnaround. Biogen and development partner Eisai reported positive data from their late-stage trial of another Alzheimer's disease candidate, lecanemab. The investigational treatment met the primary endpoint and all major secondary endpoints in a phase 3 trial.

Lecanemab showed reduction of clinical decline. This is something Aduhelm didn't clearly demonstrate. So, there's reason to be more optimistic about this newer treatment candidate -- and its ability to revive Biogen's growth. Eisai aims to apply for regulatory approval by the end of March.

Today, Biogen shares trade for about 17 times forward earnings estimates. Potential approval of lecanemab could drive the shares -- and valuation -- higher. That said, any possible disappointment in the lecanemab program could do just the opposite.

A proven winner

Keith Speights (Vertex Pharmaceuticals): All you need to do to appreciate Vertex Pharmaceuticals' resilience in a bear market is look at its stock chart. Shares of the big biotech have skyrocketed close to 40% this year, while the overall market has tanked.

I think that Vertex will keep its momentum going in 2023. All of the factors behind its impressive gain this year remain in place.

Vertex will continue to enjoy a monopoly in treating the underlying cause of cystic fibrosis (CF). Its CF drugs should have plenty of growth ahead as the company secures additional regulatory approvals in younger age groups and reimbursement deals.

Next year should bring regulatory approvals for the first CRISPR gene-editing therapy if all goes well for Vertex and its partner, CRISPR Therapeutics. That therapy, exa-cel, holds the potential to cure two rare blood disorders -- sickle cell disease and beta-thalassemia.

Vertex is also making plans for an anticipated near-term commercial launch of VX-548 in treating acute pain. The non-opioid drug should have a significant market opportunity, if approved.

Those are just Vertex's leading pipeline programs. It also has two other late-stage candidates. The company's coffers are also overflowing with cash to pursue business development deals.

The bottom line is that it doesn't matter what happens with the stock market or the economy in 2023. Vertex is a proven winner that's ready to keep on winning.

The safest bet?

Vertex and Biogen both make solid bear market bets. That's because no matter what happens with the economy, patients need their treatments. So, if these companies report positive product or pipeline news, their shares can climb even if the general market is falling.

That said, Vertex represents the safest bear market buy today. Vertex's product revenue is on the rise. And, as mentioned above, that's likely to continue. This spectacular growth should translate into share performance over the long haul.