The healthcare industry has remained a remarkably resilient place for investors to build wealth over the years. Like any industry, this one carries risk for investors to be aware of, too. Regulatory changes, payer changes, legal challenges, and the role of patents in this space are all potential risks that investors need to navigate when investing in healthcare stocks.

Nonetheless, tried-and-true healthcare businesses with a diverse lineup of market-leading products and strong financials to back them up can pose intriguing buying opportunities for long-term investors. Here are two such healthcare names to consider as you add to your stock portfolio.

1. Intuitive Surgical

Intuitive Surgical (ISRG -0.94%) has long been a leader in the field of surgical robotics, a market that is rapidly expanding as adoption of these solutions grows across various surgical specialties. The company can make anywhere from around $0.7 million to $2.5 million on a single sale of one of its flagship da Vinci surgical robotics systems.

However, Intuitive makes far more from the instruments and accessories that go with these suites, which require regular replacement. It also generates substantial revenue from various services it offers its customers, which are often hospitals and other medical providers. These services span on-demand technician services, customer support, software solutions, and more.

For every surgical procedure with its da Vinci systems, Intuitive Surgical earns anywhere from $700 to $3,600 in revenue from instruments and accessories. Service contracts for its robotic suites generate annual fees in the ballpark of $80,000 to $200,000 per system. In addition to recurring revenue from instruments, accessories, and services, Intuitive Surgical gets recurring revenue from operating leases for systems that customers don't buy outright.

The company has the same business model for its Ion system, a more recent addition to its portfolio, which is approved for use specifically in minimally invasive lung biopsies. In 2023, Intuitive Surgical brought in revenue of $7.1 billion, up 14% from one year ago. Its net income of $1.8 billion represented a 35% year-over-year bump.

Of that revenue total, $1.7 billion was derived from system sales or sales-type leases, while $4.3 billion came from instruments and accessories. Services brought in $1.2 billion in revenue for the business in 2023.

Over the trailing 12 months, Intuitive Surgical raked in $1.8 billion in operating cash flow. Levered free cash flow for that same period totaled $779 million. If you're looking for a reliable healthcare business model with multiple streams of recurring income, and a solid runway of growth still ahead, Intuitive Surgical satisfies on all counts.

2. Vertex Pharmaceuticals

Vertex Pharmaceuticals (VRTX -0.08%) is a leader in cystic fibrosis therapies, with a portfolio of medicines that raked in profits of $3.6 billion on revenue of $9.9 billion in 2023 alone. All of Vertex's approved cystic fibrosis drugs fall into a class of medicines known as cystic fibrosis transmembrane conductance regulator (CFTR) modulators. CFTR modulators work to correct the underlying genetic cause of cystic fibrosis. To date, Vertex is the only company with approved CFTR modulators on the market.

Its top-selling drug is Trikafta, a CFTR modulator that accounted for $8.9 billion (or about 90%) of Vertex's total revenues in 2023. Trikafta sales rose 16% in 2023 from the prior year, and look on track to hit the $10 billion annual sales milestone in the coming year. Even though Trikafta was only approved in 2019, its approval covered about 90% of the cystic fibrosis patient population at that time. Label expansions since that time have driven sales growth forward. Now, cystic fibrosis patients as young as two years of age with certain gene mutations can take Trikafta.

That doesn't mean the addressable market opportunity for Vertex is anywhere close to tapped out, though. Management estimates that there are upwards of 92,000 patients in North America, Europe, and Australia who could benefit from its cystic fibrosis medicines. The addressable market in those regions is up from management's previous estimate of 88,000 people several quarters ago. This rapidly growing market opportunity is partly a function of the fact that CFTR regulators are helping patients live longer, which in turn extends the need and demand for these medicines.

Vertex is working on a new triple-combination therapy that it expects to seek approval for this year. Clinical trials have shown this therapy to be even more effective than Trikafta. Management estimates that the therapy could be ideally suited for patients who are already taking drugs like Trikafta, as well as a patient population of roughly 6,000 people who have had to stop taking CFTR modulators.

Vertex is also working on an mRNA-based cystic fibrosis drug with Moderna for patients who can't take CFTR modulators at all, a patient population that management estimates is at around 5,000 people.

Cystic fibrosis is far from the only market opportunity that Vertex is setting its sights on these days. The company just garnered the distinction of being the first in history, along with its development partner CRISPR Therapeutics, to have a CRISPR-based therapy approved. The new therapy, called Casgevy, is a potential one-time functional cure for both sickle cell disease and transfusion-dependent beta thalassemia.

Vertex is also working on potential functional cures for other rare diseases, including APOL1-mediated kidney disease and Duchenne muscular dystrophy. There's a lot for investors to like about this stock right now. A buy-and-hold investment could pay off big time in the next decade and beyond.