Merck & Co., Inc. (MRK) — Q2 2026 Earnings Preview

1. Earnings Preview

Key Takeaway: The setup is modestly constructive — consensus is a manageable bar, the Q1 wholesaler timing benefit in KEYTRUDA does not repeat in Q2, but WINREVAIR momentum and KEYTRUDA QLEX J-code acceleration should offset; the single biggest swing factor is whether OHTUVAYRE's March prescription recovery translated into a meaningful Q2 revenue step-up.

Heading into Q2 2026 results, Merck faces a nuanced setup: the Street is looking for total revenue of $16.33B (+3.4% YoY) and non-GAAP EPS of -$0.11 (depressed by the ~$5.8B Terns acquisition charge taken in Q2), with the underlying business performing well above that headline figure. The bar on KEYTRUDA is fair — Q1 benefited from ~$250M in U.S. wholesaler timing that management explicitly flagged would not recur in Q2, so the Street has already adjusted; consensus sits at ~$8.37B for KEYTRUDA, implying mid-single-digit growth, which is achievable given continued metastatic demand and accelerating QLEX adoption following the April 1 permanent J-code. Management's tone since the April 30 Q1 call has been consistently bullish — the ASCO investor event on June 1 reiterated confidence in KEYTRUDA's durability, sac-TMT delivered two Phase 3 wins (TroFuse-005 in endometrial cancer and OptiTROP-Lung05 in NSCLC), and the FDA approved Lipfendra (enlicitide) on July 16, adding a near-term commercial catalyst. Estimate revisions have been broadly stable-to-rising since Q1, with FY2026 revenue consensus at ~$66.9B tracking toward the upper half of the $65.8–$67.0B guidance range, suggesting the Street is already pricing in modest upside. The stock has re-rated sharply — up ~17% since the April 30 print to ~$127.80 — driven almost entirely by multiple expansion (EV/EBITDA expanded from ~11.65x to ~13.23x over three months), meaning the stock has priced in execution; any miss on OHTUVAYRE recovery or WINREVAIR sequential growth could pressure the multiple. The key wildcard is OHTUVAYRE: management guided for H2 acceleration after a Q1 CMS-reimbursement-driven setback, and Q2 is the first quarter where prescription recovery (which began in March) should show up in revenue — a meaningful beat here would validate the COPD franchise thesis and could be the incremental positive surprise.

2. KPIs & Consensus Expectations

Key Takeaway: Consensus is a manageable bar on KEYTRUDA (no wholesaler tailwind baked in) but a higher bar on WINREVAIR given the strong Q1 beat; OHTUVAYRE is the bigger swing factor — any sequential step-up above the ~$171M consensus would be a positive read-through on the COPD recovery thesis.

Table 1 — Q2 2026 Current Quarter Snapshot (All Key KPIs)

Sources: Visible Alpha Consensus and Actuals Data (Sales, EPS — Diluted — Operating, Total revenue — Keytruda, Winrevair — Product, Capvaxive V-116, Ohtuvayre, Gardasil/Gardasil 9); MRK Q1 2026 Earnings Release (April 30, 2026); MRK Q1 2026 Earnings Call Transcript.

Note: Q2 2026 non-GAAP EPS is depressed by the ~$5.8B / ~$2.35 per share one-time R&D charge from the Terns Pharmaceuticals acquisition (closed May 2026). Underlying business EPS, excluding this charge, is estimated at approximately $1.20–$1.30. FY2026 guidance of $5.04–$5.16 excludes the Terns charge. OHTUVAYRE Q2 2025 actual is estimated from the trajectory (product launched Q3 2024 via Verona Pharma acquisition in October 2025; prior year period not directly comparable).

Table 2 — Beat / Miss History (Last 8 Quarters, Top 2 KPIs)

Top 2 KPIs: Total Revenue and KEYTRUDA Revenue (the two metrics most frequently questioned by analysts and most directly tied to management forward guidance).

Panel A: Total Revenue

Panel B: KEYTRUDA Revenue

Pattern: MRK has beaten total revenue consensus in 6 of the last 7 reported quarters; KEYTRUDA has been more mixed (4 beats, 2 misses in last 6 quarters), with misses concentrated in quarters where wholesaler timing was unfavorable — Q2 2026 consensus already strips out the Q1 timing benefit, making the bar more achievable.

Source: Visible Alpha Consensus and Actuals Data.

3. Guidance & Commentary Evolution

Key Takeaway: Guidance was raised modestly at Q1 (April 30) and has not been formally revised since; the Terns acquisition charge (~$2.35/sh) was excluded from the updated EPS range, and the Street has absorbed it — tone from the June 1 ASCO event and July 16 Lipfendra approval has been incrementally positive, with no guidance cuts.

Source: MRK Q1 2026 Earnings Call Transcript (April 30, 2026); MRK Q1 2026 Earnings Release; MRK ASCO Investor Event Transcript (June 1, 2026); Visible Alpha Consensus and Actuals Data.

4. Guidance vs. Estimate Revision Tracker

Key Takeaway: Estimates for Q2 2026 revenue have been broadly stable since the Q1 print (+0.3% for revenue), while FY2026 revenue consensus has drifted slightly higher (+0.4%), suggesting the Street is incrementally more confident in the top-line trajectory; the gap between consensus and guidance midpoint is narrow, implying limited cushion if execution disappoints.

Revenue estimates have drifted modestly higher since the Q1 print, tracking toward the upper half of guidance, while the EPS consensus decline reflects the Terns charge being incorporated post-close (May 2026) — on an underlying basis, EPS estimates are stable and consistent with the $5.04–$5.16 guidance range.

Source: Visible Alpha Consensus and Actuals Data (as-of date May 7, 2026 and current); MRK Q1 2026 Earnings Release.

5. Stock Performance

Key Takeaway: The +17% rally since the April 30 Q1 print has been driven almost entirely by multiple expansion (EV/EBITDA +13.5% over 3 months) rather than estimate revisions (+0.4% revenue), suggesting the market is re-rating MRK on pipeline confidence — this makes the stock more vulnerable to any execution miss at Q2.

Stock Price Performance — MRK vs. XLV vs. S&P 500 (Since Q1 2026 Earnings, April 30, 2026)

Sector ETF: XLV (Health Care Select Sector SPDR ETF) — appropriate for MRK's large-cap diversified pharma sub-sector.

Key Events Since Q1 Print (April 30, 2026):

• May 22, 2026: MRK surged ~8% in a single session on sac-TMT TroFuse-005 Phase 3 win (endometrial cancer OS + PFS benefit) — first TROP2 ADC to show both endpoints.
• June 1, 2026: ASCO Investor Event — management reiterated KEYTRUDA confidence, QLEX J-code acceleration, and pipeline derisking ahead of schedule.
• June 25–26, 2026: Cluster of positive catalysts (OptiTROP-Lung05 NSCLC Phase 3 win + Lipfendra CORALreef AddOn data) drove a 2-day +7.8% move.
• July 16, 2026: FDA approved Lipfendra (enlicitide) — oral PCSK9 inhibitor; stock +3.3% on the day, outperforming XLV and SPY.
• August 3, 2026: AIDS Investor Event — positive Phase 3 data for islatravir/lenacapavir (once-weekly oral HIV treatment); stock -1.9% on the day (pre-earnings caution).

Valuation Context: NTM EV/EBITDA of 13.2x vs. 7.1x one year ago (+86% multiple expansion over 12 months); NTM P/E of 18.8x. The 12-month stock return of +63.6% has been driven predominantly by multiple re-rating (+86% EV/EBITDA expansion) rather than estimate revisions, underscoring that the stock is now pricing in execution on the pipeline transformation narrative.

Source: Stock Price Data (Yahoo Finance); MRK Stock Performance Decomposition (NTM consensus multiples, trading-day windows).

6. Material News & Developments

Key Takeaway: The most important development since Q1 earnings is the FDA approval of Lipfendra (enlicitide) on July 16 — the first oral PCSK9 inhibitor approved in the U.S. — which opens a large cardiometabolic franchise and validates Merck's post-KEYTRUDA diversification thesis ahead of the print.

• July 16, 2026 — FDA Approves Lipfendra (Enlicitide): Merck received U.S. approval for Lipfendra, the first oral once-daily PCSK9 inhibitor, for LDL-C reduction. Approved ahead of the H2 2026 target management had guided. Implication: Opens a large cardiometabolic franchise; management has sized the oral PCSK9 market as a multi-billion-dollar opportunity; early launch commentary will be a key Q2 call topic.
• July 24, 2026 — MK-8527 (Monthly Oral PrEP) Access Announcement: Merck announced voluntary licensing agreements covering 129+ countries for MK-8527 (Ala), its investigational monthly oral HIV prevention pill, ahead of potential approval. Implication: Signals confidence in approval trajectory; access strategy de-risks commercial launch in low/middle-income countries.
• August 3, 2026 — AIDS 2026 Investor Event (Rio de Janeiro): Merck presented positive Phase 3 data from ISLEND-1 and ISLEND-2 (islatravir/lenacapavir once-weekly oral HIV treatment) — non-inferior to BIKTARVY with >90–95% viral suppression and no treatment-emergent resistance. Gilead leads U.S. commercialization; Merck leads ex-U.S.; revenues shared 50/50 up to $2B then 65/35 (Gilead/Merck). Implication: Validates the HIV franchise as a >$5B revenue opportunity by mid-2030s; regulatory filing planned “as quickly as possible.”
• July 20, 2026 — Barron’s KEYTRUDA Patent Cliff Coverage: Multiple Barron’s articles highlighted KEYTRUDA’s approaching patent cliff and the role of ADCs (sac-TMT) and bispecifics as successors. Implication: Investor focus on post-LOE trajectory is elevated; management will likely address the “more of a hill than a cliff” narrative on the Q2 call.
• June 25–26, 2026 — OptiTROP-Lung05 Phase 3 Win (NSCLC): sac-TMT plus pembrolizumab demonstrated highly significant PFS benefit vs. pembrolizumab alone in PD-L1-positive first-line NSCLC. Gilead’s competing TROP2 ADC (Trodelvy + KEYTRUDA, KEYNOTE-D46/EVOKE-03) was discontinued June 8 after failing to meet PFS significance. Implication: Reinforces sac-TMT’s differentiation; management will likely frame this as a cornerstone ADC with broad NSCLC applicability.
• June 19, 2026 — WELIREG + KEYTRUDA PDUFA Date: FDA PDUFA date for WELIREG in combination with KEYTRUDA/KEYTRUDA QLEX in adjuvant RCC (LITESPARK-022). If approved, would be the first IO combination in adjuvant RCC. Implication: Potential label expansion for both WELIREG and KEYTRUDA; approval outcome will be discussed on the Q2 call.
• June 1, 2026 — ASCO Investor Event: Management reiterated >$25B non-risk-adjusted commercial opportunity from oncology late-stage pipeline by mid-2030s (excl. Terns); confirmed KEYTRUDA QLEX adoption accelerating post-J-code; highlighted sac-TMT TroFuse-005 as first TROP2 ADC to show both OS and PFS benefit in endometrial cancer. Implication: Tone was the most bullish since the transformation narrative began; pipeline derisking ahead of schedule.
• May 2026 — Terns Pharmaceuticals Acquisition Closed: Merck closed the acquisition of Terns Pharmaceuticals (TERN-701 / MK-4208, oral allosteric BCR::ABL1 inhibitor for CML). One-time R&D charge of ~$5.8B (~$2.35/sh) will hit Q2 2026 reported EPS. FDA granted Breakthrough Therapy Designation for MK-4208. Implication: Q2 headline EPS will be deeply negative; investors should focus on underlying EPS excluding the charge.
• June 30, 2026 — National Security Probe (China Trials): Reports emerged of national security probes into Merck and AbbVie over China clinical trial activities. Implication: Potential regulatory/geopolitical risk; GARDASIL China demand already depressed; management may address on the call.

7. Peer Commentary & Current-Quarter Read-Throughs

Methodology Note: This section includes only peer commentary from the period June 5 – August 4, 2026 that explicitly addresses the peer’s then-current quarter (Q2 2026) or forward remainder-of-2026 outlook. Retrospective commentary about previously reported quarters (e.g., Q1 2026 results discussed on Q1 earnings calls) is excluded. Conference commentary from Goldman Sachs Global Healthcare Conference (June 8–9, 2026) and AstraZeneca’s Q2 2026 earnings call (July 27, 2026) and Bristol-Myers Squibb’s Q2 2026 earnings call (July 30, 2026) are included as they contain forward-looking statements about the then-current or upcoming quarter.

7.1 Oncology / KEYTRUDA Read-Throughs

AstraZeneca — Q2 2026 Earnings Call (July 27, 2026)

Read-Through Signal: Positive for KEYTRUDA demand and oncology pricing environment.

• AZN confirmed its oncology business is “well positioned for continued growth through the rest of the year” with strong momentum across the portfolio — a positive read-through for the broader oncology market in which KEYTRUDA competes.
• AZN’s oral PCSK9 program noted it hopes for “a competitive profile versus the compound of Merck” — an explicit acknowledgment that Lipfendra (enlicitide) is the benchmark, validating Merck’s first-mover advantage in oral PCSK9.
• AZN’s Claudin 18.2 ADC (Sony Vedotin) Phase 3 win (Clarity Gastrica-1) with estimated peak revenue of $3–$5B reinforces the ADC market’s commercial viability — positive read-through for sac-TMT’s commercial potential.
• AZN’s pricing commentary noted “productive engagement with payers” under the MFN framework, with the direction of travel being “US prices to come down a bit, wealthy nation prices to come up” — a manageable pricing environment for Merck’s U.S. portfolio.

Bristol-Myers Squibb — Q2 2026 Earnings Call (July 30, 2026)

Read-Through Signal: Mixed — positive for oncology market demand; neutral-to-negative for KEYTRUDA competitive dynamics in hematology.

• BMY’s growth portfolio grew +14% YoY in Q2 2026 with 10 products achieving double-digit growth — confirms robust oncology market demand broadly, a positive read-through for KEYTRUDA’s continued uptake.
• BMY’s Opdualag (LAG-3 + PD-1) delivered “another quarter of strong double-digit growth” driven by global demand and its leading position in first-line melanoma — confirms the IO combination market is growing, which is relevant for KEYTRUDA’s combination strategies.
• BMY’s Iberdomide (cell mod) has an August 17, 2026 PDUFA date — same day as KEYTRUDA + Padcev PDUFA for cisplatin-eligible MIBC. BMY’s hematology launches (Iberdomide, Mezigdomide) are in settings where KEYTRUDA has limited overlap, so competitive impact on MRK is minimal.
• BMY noted “typical summer demand patterns to moderate growth in Q3” — a mild caution for Q3 but not Q2; no negative read-through for MRK’s Q2 print.
• BMY’s Reblozyl grew +29% in Q2 in MDS and MF — confirms the hematology market is healthy, a positive backdrop for MRK’s emerging hematology pipeline (nemtabrutinib, bomedemstat, MK-4208).

7.2 HIV / Infectious Disease Read-Throughs

Gilead Sciences — Goldman Sachs Global Healthcare Conference (June 9, 2026)

Read-Through Signal: Positive for MRK’s HIV franchise; validates islatravir/lenacapavir commercial opportunity.

• Gilead confirmed it “just got the news yesterday that the once-weekly islatravir/lenacapavir program with Merck was successful from a clinical trial perspective” (June 8, 2026 — the day before the conference) — this is the ISLEND-1/ISLEND-2 data that Merck formally presented at AIDS 2026 on August 3. Gilead framed it as providing “the first kind of long-acting treatment regimen.”
• Gilead raised its full-year 2026 YEZTUGO (lenacapavir PrEP) guidance from $800M to $1B following strong Q1 performance — confirms the long-acting HIV prevention market is growing rapidly, a positive backdrop for MRK’s MK-8527 (monthly oral PrEP) program.
• Gilead noted the HIV treatment market was ~$26B in 2025 and expected to grow to ~$32B by mid-2030s — consistent with MRK’s >$5B HIV revenue target by mid-2030s being achievable within a growing market.
• Gilead acknowledged that long-acting treatments will “cannibalize BIKTARVY over time” — this is the market dynamic that creates the opportunity for MRK’s islatravir-based regimens to capture switch patients.
• Gilead’s commercialization structure for islatravir/lenacapavir: Gilead leads U.S., Merck leads ex-U.S., revenues shared 50/50 up to $2B then 65/35 (Gilead/Merck) — confirmed by both companies; MRK’s ex-U.S. leadership is a meaningful commercial opportunity given the global HIV burden.

7.3 Cardiovascular / PCSK9 / Pulmonary Hypertension Read-Throughs

Pfizer — Goldman Sachs Global Healthcare Conference (June 8, 2026)

Read-Through Signal: Positive for WINREVAIR’s competitive positioning; neutral for Lipfendra (enlicitide) given Pfizer’s PD-1/VEGF focus is in oncology, not PCSK9.

• Pfizer’s CEO highlighted its PD-1/VEGF bispecific (4404 program) as “best-in-class” with 77% response rate in PD-L1-enriched NSCLC vs. KEYTRUDA’s 45% — a competitive signal for KEYTRUDA in first-line NSCLC, though Pfizer’s program is still in Phase 3 and MRK’s sac-TMT + pembrolizumab combination (OptiTROP-Lung05) already has Phase 3 data.
• Pfizer noted “significant upside in the non-COVID business” for the remainder of 2026 — confirms the broader pharma commercial environment is healthy, a positive read-through for MRK’s new product launches.
• Pfizer’s pricing commentary: the MFN deal provides a “holiday of any tariffs” and applies MFN “prospective only for new products with Medicaid” — a manageable pricing environment for MRK’s new launches (Lipfendra, WINREVAIR, CAPVAXIVE).

AstraZeneca — Q2 2026 Earnings Call (July 27, 2026) — Oral PCSK9 Commentary

Read-Through Signal: Positive for Lipfendra’s first-mover advantage; AZN’s oral PCSK9 Phase 3 readout not until H1 2027.

• AZN explicitly stated it hopes for “a competitive profile versus the compound of Merck” for its oral PCSK9 — confirming Lipfendra is the benchmark and that AZN’s program is at least 6–12 months behind. Implication: MRK has a meaningful first-mover window in oral PCSK9 with no approved competitor until at least H1 2027.

7.4 Amgen — Goldman Sachs Global Healthcare Conference (June 9, 2026)

Read-Through Signal: Positive for the broader oncology and cardiovascular market; limited direct read-through for MRK’s specific products.

• Amgen characterized 2026 as a “springboard year” with rapidly growing products expected to offset denosumab competition — confirms the large-cap pharma sector is navigating LOE headwinds successfully, a positive narrative parallel for MRK’s KEYTRUDA LOE management.
• Amgen’s IMDELLTRA (DLL3 bispecific) is “annualizing at more than $1B in sales” in small cell lung cancer — relevant because MRK’s I-DXd (ifinatamab deruxtecan) has a PDUFA date of October 10, 2026 in the same indication; IMDELLTRA’s commercial success validates the SCLC market opportunity for I-DXd.
• Amgen’s olpasiran (Lp(a) reducer) Phase 3 with ~7,200 patients confirms the cardiovascular outcomes trial market is active — a positive backdrop for MRK’s cardiovascular pipeline (enlicitide, MK-2060).

Sources: AstraZeneca Q2 2026 Earnings Call Transcript (July 27, 2026); Bristol-Myers Squibb Q2 2026 Earnings Call Transcript (July 30, 2026); Gilead Sciences Goldman Sachs Global Healthcare Conference Transcript (June 9, 2026); Pfizer Goldman Sachs Global Healthcare Conference Transcript (June 8, 2026); Amgen Goldman Sachs Global Healthcare Conference Transcript (June 9, 2026).

8. Insider Transaction Activity

Key Takeaway: No open-market insider purchases or discretionary sales were identified in the SEC Form 4 database for MRK in the period surrounding the Q2 2026 earnings window (May–August 2026). The absence of notable insider buying or selling is consistent with a company in a quiet period ahead of earnings and does not send a directional signal.

Open-market buy and sell transactions (Form 4 codes P/S) were screened for MRK insiders over the May 1 – August 4, 2026 window. No open-market purchases (code P) or discretionary sales (code S) were returned from the SEC Form 4 database for this period. This is consistent with the standard pre-earnings quiet period observed by large-cap pharmaceutical companies. Any transactions that may have occurred under pre-established 10b5-1 plans would be disclosed on Form 4 with the “plan” flag; none were identified in the data pull.

Source: SEC Form 4 Filings Database (insider_transactions dataset, transaction codes P/S, MRK, May 1 – August 4, 2026).

Appendix: Key Estimates Summary

All consensus estimates sourced from Visible Alpha Consensus and Actuals Data. Actuals sourced from MRK Q1 2026 Earnings Release (April 30, 2026) and MRK Q1 2026 Earnings Call Transcript. FY2026 guidance sourced from MRK Q1 2026 Earnings Release. Peer commentary sourced from company earnings call transcripts and conference transcripts as cited in Section 7.

Disclaimer: This document is prepared for informational purposes only. All estimates are consensus figures from Visible Alpha and do not represent the views of the preparer. Forward-looking statements are subject to material risks and uncertainties.