The 15 Specialty Drugs Driving Half of Your Employer Pharmacy Spend

Here's something most benefits brokers will never show you — but every CFO and HR leader managing a self-funded or level-funded health plan should know:

You don't need to track hundreds of drugs to understand your pharmacy spend. 

You need to track 15.

In employer health plans across the country, a small number of specialty medications account for a disproportionate share of total pharmacy costs. Industry data consistently shows that specialty drugs — used by roughly 2% of plan members — now account for more than 50% of total pharmacy spending, with projections putting that figure above 60% by the end of 2026. And within that specialty category, a specific watchlist of 15 drugs tends to drive the majority of employer spend, plan after plan, year after year.

Benefits consultants at major firms have tracked this list for years. Most employers and their brokers haven't.

That's the gap Evolve Benefits was built to close, and it's exactly what Rx Shield™ at www.myrxshield.com was designed to address.

Why Specialty Drug Spend Is the Defining Benefits Challenge of 2026

Before we get to the list, the broader context matters.

Specialty drugs are used by roughly 2% of plan members but account for more than 50% of total employer pharmacy spending… a figure projected to exceed 60% in 2026. Per-member-per-year specialty drug costs rose from $1,333 in 2023 to $1,641 in 2024, a 23% increase in a single year, according to the Pharmaceutical Strategies Group's 2025 State of Specialty Spend and Trend Report. At the same time, the number of specialty drugs in development has exploded, as by mid-2024, specialty medications represented approximately 75% of the roughly 7,000 new drugs under development. 

The pipeline is not slowing down. It is accelerating.

For employers, this isn't an abstract market trend. It lands directly in your claims. In many mid-market employer health plans — those covering workforces with $25M to $150M in payroll — just five specialty drugs can account for 40% to 60% of total pharmacy spend. And because specialty drug utilization is concentrated among a small number of employees, a single new claimant can reshape your entire pharmacy trend in one plan year.

The top three specialty drug spend categories for employers have remained consistent: inflammatory disorders, oncology, and multiple sclerosis. GLP-1 medications have rapidly become a fourth force, with utilization increasing and showing no signs of leveling off.

Tracking the 15 drugs that drive this spend gives employers, and their benefits partners, a decisive strategic advantage. You can see risk building before it becomes a claims problem. You can evaluate whether biosimilar alternatives, step therapy, site-of-care optimization, or specialty carve-outs are appropriate. And you can have data-driven conversations about plan design rather than reacting to a renewal increase that has no clear explanation attached.

The 15 Specialty Drugs Every Employer Plan Should Be Tracking

Immunology & Autoimmune Biologics

Typical annual cost: $40,000 – $120,000 per patient

These six drugs alone represent tens of billions in annual U.S. drug spending and are the dominant force in employer specialty pharmacy claims. The top three categories for specialty drug spend have remained unchanged for years, and inflammatory disorders sit at the top of that list.

1. Humira (adalimumab) Used for rheumatoid arthritis, Crohn's disease, psoriasis, and several other autoimmune conditions. Biosimilars have launched and are gaining formulary traction, but branded Humira remains widely utilized. Managing biosimilar substitution here is one of the highest-ROI strategies in specialty drug management.

2. Dupixent (dupilumab) Manufacturer: Sanofi / Regeneron. Used for atopic dermatitis, asthma, chronic sinusitis, and — increasingly — COPD. New indications are expanding the eligible patient population rapidly, making this one of the fastest-growing specialty drugs in employer plans.

3. Stelara (ustekinumab) Crohn's disease, ulcerative colitis, psoriasis. Multiple biosimilars launched in early 2025. Employers with active biosimilar programs are seeing meaningful cost reductions here — those without are still paying full biologic rates.

4. Skyrizi (risankizumab) AbbVie's next-generation biologic for psoriasis, Crohn's, and ulcerative colitis. Rapidly replacing older medications in this class. Annual cost often exceeds $80,000, and unlike some competitors, biosimilar alternatives are not yet available.

5. Enbrel (etanercept) A longstanding rheumatoid arthritis and psoriasis treatment. One of the 10 drugs selected for Medicare price negotiation under the Inflation Reduction Act, with negotiated prices taking effect January 2026. Employers should be evaluating how this affects their PBM contract terms.

6. Cosentyx (secukinumab) Used for psoriasis, psoriatic arthritis, and ankylosing spondylitis. One of the top ten drugs driving increased prescription plan costs heading into 2026, per industry benefit benchmarking data.

GLP-1 & Metabolic Medications

Typical annual cost: $10,000 – $16,000 per patient

The fastest-growing pharmacy spend category in employer health plans, and the one generating the most urgent coverage policy conversations.

7. Ozempic (semaglutide) Originally approved for type 2 diabetes, now widely used off-label for weight loss. Semaglutide drugs generated over $38 billion in U.S. spending recently, with Ozempic brand recognition driving demand disproportionately toward this specific formulation.

8. Wegovy (semaglutide) The same molecule as Ozempic, approved specifically for obesity management. Expanding indications, including cardiovascular risk reduction, are broadening eligibility significantly. Employers without a defined Wegovy coverage policy are writing an open-ended check.

9. Mounjaro / Zepbound (tirzepatide) Eli Lilly's GLP-1 entry, approved for both diabetes (Mounjaro) and obesity (Zepbound). Clinical data suggests it may be more effective than semaglutide for weight loss, which is accelerating utilization. Consultants project obesity GLP-1s could reach $100 billion or more in annual U.S. spending later this decade.

10. Trulicity (dulaglutide) An older GLP-1 used primarily for type 2 diabetes. Lower cost than Ozempic or Mounjaro, making it an important formulary management and step therapy option for employers building a GLP-1 coverage strategy.

11. Jardiance (empagliflozin) An SGLT2 inhibitor used for type 2 diabetes and heart failure. Increasingly common in employer plans due to the growing prevalence of cardiometabolic conditions in working-age populations. Relevant both as a standalone cost driver and as an alternative to GLP-1 step therapy programs.

Oncology & Ultra-Specialty

Typical annual cost: $80,000 – $200,000+ per patient

These drugs drive the highest per-patient costs in employer health plans. A single employee on a high-cost oncology therapy can equal the pharmacy spend of hundreds of other plan members.

12. Keytruda (pembrolizumab) Merck's blockbuster cancer immunotherapy — currently the world's top-selling drug — approved for dozens of cancer types. Annual therapy regularly exceeds $150,000. Patent expiration is anticipated around 2028, with multiple biosimilar developers already in the pipeline, but near-term cost relief for employer plans is limited.

13. Revlimid (lenalidomide) Used for multiple myeloma and certain blood cancers. Generic versions are now available but adoption has been inconsistent depending on PBM formulary management. Employers with strong PBM oversight are capturing savings here.

14. Ibrance (palbociclib) A targeted therapy for hormone receptor-positive breast cancer. Annual costs can exceed $150,000. As breast cancer survival rates improve and treatment durations extend, this drug's presence in employer claims is growing.

15. Xtandi (enzalutamide) Used for prostate cancer at multiple stages of disease progression. One of the more common ultra-specialty oncology drugs appearing in mid-market employer health plans, and a driver of stop-loss carrier attention in self-funded arrangements.

What This List Actually Tells You

The value of tracking these 15 drugs isn't academic — it's operational. 

Here's the strategic intelligence this watchlist unlocks:

Biosimilar opportunity: Humira, Stelara, and Enbrel all have biosimilar alternatives now available. If your plan is still paying branded rates for these medications without a documented biosimilar management strategy, you have a recoverable cost sitting in your claims right now.

GLP-1 exposure: If your plan covers Ozempic, Wegovy, or Mounjaro without defined clinical criteria, prior authorization, or utilization limits, your exposure is open-ended. The question isn't whether these drugs will affect your plan — it's whether you have a strategy in place before they do.

Oncology risk: One employee on Keytruda or Ibrance can represent more pharmacy spend than 200 other plan members combined. Stop-loss carriers are paying close attention to oncology exposure. You should be too.

PBM and rebate leverage: Several of these drugs, particularly the immunology biologics, generate significant manufacturer rebates that flow through PBMs. How much of that rebate is passing through to your plan? If you don't know the answer, that's a conversation worth having.

Site-of-care optimization: Many of these medications, particularly the immunology biologics and oncology drugs, are administered as infusions. Where those infusions take place has an enormous impact on what your plan pays. See our previous blog on infusion drug markups for a full breakdown of this opportunity.

This Is What Evolve's Rx Shield™ Program Tracks for You

The employers who manage specialty drug spend most effectively share one thing in common: they're not reacting to their pharmacy trend at renewal. They're watching it in real time, every month, against a known watchlist and making plan design and vendor decisions accordingly.

That's the exact discipline that Rx Shield™ at www.myrxshield.com brings to Evolve's employer clients.

Through Rx Shield, we:

• Identify your top specialty Rx spend drivers by analyzing your claims data against the drugs most likely to be generating hidden cost in your plan (including the 15 on this list).

• Reduce your top Rx spend through targeted interventions: biosimilar management, GLP-1 coverage policy design, specialty carve-outs, step therapy programs, PBM contract review, and site-of-care optimization

• Monitor your specialty drug trend year-round so cost surprises don't arrive for the first time at your renewal meeting

Most employers don't find out they have a specialty drug problem until it shows up as a double-digit premium increase with no clear explanation. By then, the cost has already occurred. The strategy should have been in place the year before.

The 15 drugs on this list are where most of that cost originates. Knowing which ones are active in your plan — and having a strategy for each — is the difference between managing your pharmacy spend and simply absorbing it.

The Bottom Line

Specialty drugs are now the primary driver of employer health plan pharmacy costs, and the trend is accelerating. With GLP-1 medications expanding into new indications, gene therapies entering the market at record pace, and oncology drugs continuing to rise in both cost and utilization, specialty medications are projected to account for more than 60% of total pharmacy spending in 2026 — despite representing fewer than 5% of all prescriptions written.

You cannot manage what you cannot see. And most employers — and most brokers — are not looking at this with the specificity the problem demands.

The 15 drugs in this post are where to start. And Evolve Benefits, with Rx Shield, is built to take it from there.

Visit www.myrxshield.com or reach out to Evolve directly. We'll show you exactly which of these drugs are active in your plan, what they're costing you, and what a targeted strategy looks like. 

Your next premium increase is coming — let's get ahead of it together.

Sources: Pharmaceutical Strategies Group, Artemetrx State of Specialty Spend and Trend Report (August 2025); CarelonRx Specialty Drug Growth Analysis; INSURICA 2026 Specialty Drug Surge Report; OpenLoop Health, "What High-Cost Specialty Drugs Will Affect Premiums in 2026" (December 2025)