This year has been tough for most stocks -- even the biggest and strongest of names. All three major indexes slipped into bear territory. And economic problems like rising inflation weighed on earnings across industries.

Still, this year brought us a few exceptions. Some companies managed to deliver good news -- and strong stock performance. Investors, confident in these companies' stories, piled into the shares. And in some cases, it's not too late to get in on these players.

In fact, buying two of these unstoppable stocks before 2023 could be a genius move. That's because next year could be a key turning point for them.

1. Vertex Pharmaceuticals

Vertex Pharmaceuticals (VRTX -0.57%) is the global leader in cystic fibrosis (CF) treatments. The company's four commercialized drugs bring in billions of dollars annually in revenue and profit. Even better, the company predicts its leadership should continue until at least the late 2030s.

Vertex's latest CF drug, Trikafta, still has plenty of revenue growth ahead. That's as it wins reimbursements in additional countries and approvals in younger age groups.

The company also is studying a new CF candidate in phase 3 trials that may be even better than Trikafta. And Vertex is working with Moderna on the development of a CF drug for patients who can't be helped by Vertex's current treatments.

But the potential share-price catalyst in the coming year has nothing to do with the CF program. Instead, it has to do with Vertex's candidate for blood disorders, exa-cel -- a one-time curative treatment for two blood disorders with limited treatment options today. Vertex and its partner CRISPR Therapeutics are currently submitting exa-cel to regulators in the U.S., Europe, and the U.K.

An approval could be big for two reasons. First, and importantly, it would show that Vertex can succeed beyond CF. And second, it would offer Vertex an additional revenue source -- that's always welcome, even if the company is already generating billions of dollars.

Yes, Vertex has gained a lot this year; it's heading for a 38% increase. But it's still only trading at about 20 times forward earnings estimates. If Vertex scores regulatory approval for exa-cel, there's plenty of room for additional gains -- in the near term and over time.

2. Biogen

Biogen (BIIB -0.70%) has been through a difficult couple of years. The company's blockbuster multiple sclerosis drug, Tecfidera, is losing sales to generic competitors. And Biogen's hopes of making its new Alzheimer's drug Aduhelm the next big revenue driver evaporated earlier this year.

The medical community was greatly divided over Aduhelm's safety and efficacy profile. And after Medicare decided against coverage of the treatment, Biogen gave up on the program.

That left Biogen still in need of a new product to compensate for an aging product portfolio. But good news was only a few months away. Biogen and partner Eisai announced this fall that another Alzheimer's candidate -- lecanemab -- met all primary endpoints and key secondary endpoints in a phase 3 trial. Eisai aims to file for regulatory approval of the treatment by the end of March. If the drug wins a nod, the companies will split profits.

How big could lecanemab be for Biogen? Analysts forecast peak sales in the range of $6 billion to $14 billion. Biogen's annual revenue last year totaled about $10 billion, so the addition of lecanemab to its product portfolio could usher in a new era of growth.

Biogen stock is heading for an 18% gain this year. The shares now trade for about 16 times forward earnings estimates. That's very reasonable if Biogen is able to succeed with lecanemab and other pipeline programs.

Still, due to Biogen's aging product portfolio, the stock remains risky until Biogen launches a new drug to drive growth. The most cautious of investors probably should wait on this one. But if you can accept the risk, buying Biogen before the new year may be a genius move.