Another quarter, another solid performance from Vertex Pharmaceuticals (VRTX 0.20%). The big drugmaker beat consensus estimates for its Q1 results announced on Monday. Vertex's shares subsequently added even more to the nice gains already achieved so far this year.

But it's not too late for investors to jump aboard the Vertex train. Here are seven reasons to buy the stock now.

1. Recession-proof thanks to a CF monopoly

Vertex is the only company in the world with approved therapies that treat the underlying cause of cystic fibrosis (CF). Its nearest competition is only in phase 2 testing. And one previous rival -- AbbVie -- threw in the towel on its CF program this week.

With the banking crisis increasing the odds of a U.S. recession, investors would be wise to look for recession-proof stocks right now. Thanks to its CF monopoly, Vertex belongs squarely in that group.

2. An even more powerful CF therapy on the way

The company's most powerful CF therapy yet is on the way to probable regulatory approval. Vertex expects to complete late-stage testing of a triple-drug combo featuring vanzacaftor by the end of 2023.

This vanzacaftor triple won't just cannibalize sales of Vertex's other CF therapies. Chief Operating Officer Stuart Arbuckle said in the Q1 earnings call that the new therapy could help the roughly 6,000 patients who have discontinued Vertex's other drugs because of their side effects. The triple-drug combo will also be more profitable for Vertex if approved because of its significantly lower royalty structure.

3. On track to launch the first CRISPR gene-editing therapy

Vertex and CRISPR Therapeutics await U.S. and European regulatory approvals for exa-cel as a one-time functional cure for sickle cell disease and transfusion-dependent beta-thalassemia. Exa-cel is on the cusp of becoming the first CRISPR gene-editing therapy to make it to market. The therapy should become Vertex's next product to generate multibillion-dollar sales.

4. A promising non-opioid pain drug waiting in the wings

Vertex isn't just targeting rare diseases. The company also has a promising non-opioid pain drug, VX-548, waiting in the wings. VX-548 should complete late-stage testing in acute pain later this year. Vertex also thinks the drug could have significant opportunities in the chronic pain market. 

5. Targeting a new market that's bigger than CF

CF affects around 88,000 patients. Vertex is going after another market that's even bigger. The company has a pivotal clinical study in progress evaluating inaxaplin in treating APOL1-mediated kidney disease (AMKD). Around 100,000 patients in the U.S. and Europe suffer from AMKD. There is currently no approved drug for the disease.

6. A potential cure for type 1 diabetes in development

Vertex's pipeline also features three programs focused on curing type 1 diabetes. One of those programs, VX-880, is already in phase 1/2 testing. A second program, VX-264, doesn't require the immunosuppressants that VX-880 does and should begin early stage testing within a few months. Vertex and CRISPR Therapeutics are also collaborating on a gene-editing program that won't require immunosuppressants. 

7. A cash stockpile of $11.5 billion

Last, but not least, Vertex ended the first quarter of 2023 with a cash stockpile (including cash equivalents and marketable securities) of $11.5 billion. The company is using some of its cash to repurchase shares. In February 2023, Vertex's board approved a $3 billion stock buyback program.

However, CFO Charlie Wagner said in the Q1 call that the company's top priority for using its cash "continues to be investment in innovation, both internally and externally." That could mean that more growth-driving new therapies will be on the way, which will add more reasons to buy this recession-resistant stock.