Merck (NYSE: MRK) Q2 2026 Earnings Preview

Date clarification: Merck reports today, Tuesday, August 4, 2026, not tomorrow. The company’s Q2 earnings call is scheduled for 9:00 a.m. ET. (merck.com)

Executive take

Merck enters Q2 with a stronger stock backdrop and rising confidence in its post-KEYTRUDA growth portfolio—but expectations are no longer low. The investment debate for this report is less about the headline EPS number, which is likely distorted by acquisition accounting, and more about whether the company can demonstrate:

  1. Sustained KEYTRUDA growth without an outsized benefit from U.S. distributor ordering;
  2. Continued WINREVAIR momentum toward its large commercial opportunity;
  3. Containment of vaccine headwinds, particularly GARDASIL in China and Japan;
  4. A clean guide update that separates underlying operating performance from the Terns acquisition charge; and
  5. Evidence that recent approvals and pipeline progress are building credible growth engines beyond KEYTRUDA.

The latest market digest points to consensus of roughly $16.33 billion in Q2 revenue—about 3%–4% year-over-year growth—and EPS of negative $0.25, with the loss principally reflecting M&A-related charges rather than underlying operations.

The setup: strong Q1 fundamentals, but distorted reported earnings

In Q1, Merck reported $16.3 billion of sales, up 5% reported and 3% ex-FX. KEYTRUDA/KEYTRUDA QLEX sales reached $8.0 billion, up 12% reported, while WINREVAIR grew 88% to $525 million and Animal Health increased 13% to $1.8 billion. The quarter also contained a $3.62-per-share Cidara acquisition charge, producing a reported non-GAAP loss despite healthy operating performance. (merck.com)

The Q2 issue is likely similar: investors should not overread the reported EPS loss. Merck completed its acquisition of Terns on May 5, 2026; at Q1, management said the deal was expected to produce an approximately $5.8 billion one-time charge, or about $2.35 per share, plus roughly $0.12 of remaining-2026 EPS dilution from financing and development spend. The key question is whether management formally incorporates these effects into full-year guidance today—and what underlying EPS looks like after removing transaction noise. (merck.com)

What matters most in the quarter

1. KEYTRUDA: growth quality matters more than the absolute number

KEYTRUDA remains the dominant driver of Merck’s financial model. Q1 growth was strong, but management noted that U.S. results benefited from the timing of wholesaler purchases. That creates a higher bar for Q2: investors will want to see that growth remains supported by patient demand, earlier-stage penetration, international uptake, and the gradual adoption of subcutaneous KEYTRUDA QLEX—not simply channel timing.

The strategic case remains solid. Merck has continued to extend the franchise, including the July approval of KEYTRUDA/KEYTRUDA QLEX with Padcev for treatment before and after surgery in certain muscle-invasive bladder cancer patients. The company also received June approval for KEYTRUDA or KEYTRUDA QLEX plus WELIREG in adjuvant clear-cell renal-cell carcinoma. (merck.com)

What to watch - Reported versus constant-currency KEYTRUDA growth; - U.S. pricing, volume, and channel-inventory commentary; - QLEX sales and adoption trajectory; - Contribution from earlier-stage oncology and GU/women’s cancers; - Management’s framing of durability ahead of eventual KEYTRUDA loss of exclusivity.

2. WINREVAIR remains the most important near-term non-oncology growth asset

WINREVAIR generated $525 million in Q1, up 88% year over year, driven by continuing U.S. adoption and initial international uptake. It is now large enough that the pace of quarterly sequential growth—and any commentary on treated-patient expansion, persistence, and international launches—can materially influence confidence in Merck’s medium-term growth algorithm. (merck.com)

A strong WINREVAIR print would reinforce the idea that Merck’s future is not solely reliant on oncology. Conversely, a material deceleration would raise questions about the practical ceiling of the current pulmonary arterial hypertension opportunity and the timing of additional indications.

3. Vaccines are the principal commercial offset

GARDASIL/GARDASIL 9 fell 19% in Q1, including a 22% decline excluding foreign exchange, primarily due to weaker demand in China, the end of Japan’s catch-up vaccination program, and unfavorable U.S. public-sector purchasing patterns. Other vaccine franchises also faced pressure, including VAXNEUVANCE and ROTATEQ. (merck.com)

This is likely the most important downside variable in the Q2 revenue bridge. Investors should focus on whether GARDASIL trends are stabilizing, whether management sees the China weakness as cyclical or more persistent, and whether it changes the cadence of second-half growth.

4. Animal Health is becoming a meaningful stabilizer

Animal Health grew 13% in Q1, led by livestock demand, pricing, and new-product contribution in companion animals. The segment is smaller than pharmaceuticals but provides diversification, relatively dependable cash generation, and an offset to vaccine volatility. (merck.com)

The key watch item is whether companion-animal demand remains affected by lower veterinary visits, or whether pricing and launches can continue to offset that pressure.

Guidance: the most consequential call item

Merck’s Q1 outlook called for:

FY 2026 outlook set in Q1 Guidance
Revenue $65.8B–$67.0B
Non-GAAP EPS $5.04–$5.16
Non-GAAP gross margin ~82%
Non-GAAP operating expenses $36.0B–$36.8B

That EPS range already included the Cidara charge, but it did not include the anticipated impact of the then-pending Terns acquisition. (merck.com)

What would be constructive

What would disappoint

Portfolio and pipeline: positive signals, but not yet Q2 revenue drivers

Merck has entered the report with a notable sequence of recent approvals and clinical milestones:

These developments strengthen the post-KEYTRUDA narrative. Still, the near-term stock reaction is more likely to be determined by KEYTRUDA, WINREVAIR, GARDASIL, guidance, and the clarity of the acquisition-adjusted earnings bridge.

Investor checklist for the call

  1. Did KEYTRUDA beat expectations, and was the beat volume-driven?
  2. Did Q1 wholesaler timing reverse in Q2, or did underlying demand remain robust?
  3. How quickly is WINREVAIR growing sequentially, particularly outside the U.S.?
  4. Are GARDASIL declines bottoming, especially in China?
  5. Does management raise revenue guidance or merely absorb Terns-related EPS dilution?
  6. What is the normalized EPS outlook excluding Cidara and Terns charges?
  7. What early launch commentary does Merck provide for WELIREG’s new RCC indication, LIPFENDRA, and KEYTRUDA QLEX?
  8. Does management offer incremental commercial detail on the HIV opportunity following the August 3 investor event?

Bottom line

Base case: Merck delivers modest revenue growth around consensus, led by KEYTRUDA, WINREVAIR, and Animal Health, while reported EPS is obscured by the Terns acquisition charge. The most favorable outcome is a reaffirmation or increase in underlying revenue expectations combined with confidence that vaccine pressure is manageable.

Bull case: KEYTRUDA demand proves cleaner than feared after Q1 ordering dynamics, WINREVAIR remains on a steep sequential ramp, GARDASIL stabilizes, and management frames recent approvals—especially LIPFENDRA—as meaningful additions to the medium-term growth outlook.

Bear case: KEYTRUDA growth slows more sharply than expected, vaccine weakness worsens, WINREVAIR decelerates, or guidance implies that the company’s acquisition strategy is creating greater-than-expected drag on normalized earnings.

This preview is for informational purposes only and is not investment advice.