Was There Any Sign Merck Stock Would Run?

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Merck (MRK) stock returned 78.7% in the twelve months to October 21, 2026, against 16.5% for the S&P 500. Over that year, Merck reported fast growth from its newer drugs, which management expects to carry the company past the end of exclusivity for Keytruda, its big cancer drug. So what could you have seen of Merck’s newer drugs before October 2025?

Merck Pointed To Its Newer Drugs Early In 2025

Management pointed to these newer treatments on the fiscal Q4 2024 call on February 4, 2025, more than eight months before the period measured here. Management said Merck was moving rapidly toward a much more diversified portfolio, and that its plan to get through the end of Keytruda’s exclusivity was unchanged. This signaled management’s strategy to diversify the revenue base well ahead of newer commercial contributions reflecting in top-line growth.

By the fiscal Q2 2025 call on July 29, 2025, management was able to put a number on one of those drugs. Management said Winrevair, the company’s treatment for pulmonary arterial hypertension, continued its strong momentum with global sales of $336 million in the quarter. While this was just one product, it put a figure behind what management had said in February.

Merck’s own totals were weaker. Revenue fell 1.6% from a year earlier in the quarter ended in March 2025, and 1.9% in the quarter ended in June 2025. Even so, the shares rose 13.1% in the six months to October 20, 2025, meaning the stock was already rising before the period measured here. The early signs emerged from what management said and from one drug’s sales, rather than in Merck’s totals.

A run like this can leave Merck a much larger share of what you own than you planned. See how to protect a concentrated position.

What Had Changed At Merck By Mid-2026?

By the quarter ended in June 2026, Merck’s revenue was growing again, rising 5.1% from a year earlier to $16.6 billion. Winrevair’s global sales reached $588 million in that quarter, accounting for about 3.5% of revenue. Welireg, a kidney cancer drug, had sales of $271 million, up 67%.

Keytruda still brought in about half of Merck’s revenue, with sales of the Keytruda family reaching $8.4 billion in the same quarter. The newer drugs grew fast, but they remained small beside Keytruda.

Is Merck Still Pointing To Its Newer Drugs?

Merck is, and it now also points to drugs still in development. During the fiscal Q2 2026 call on August 4, 2026, management said its confidence was higher than in January. In January, management had not expected results from two cancer drugs in development until 2027. Both had since produced positive results, though in September 2026 Merck and Daiichi Sankyo withdrew their U.S. filing for one of them, I-DXd, in a type of lung cancer.

Management also expects U.S. Keytruda growth to slow as the drug reaches its peak share in several of its main uses. Management described the end of Keytruda’s exclusivity as “more of a hill than a cliff.” A slower Keytruda would leave more of Merck’s growth to its newer drugs.

Merck faces a harder comparison in the third quarter of 2026. Management said Merck gained about $250 million from the timing of wholesaler purchases in the third quarter of 2025, a gain it does not expect again in 2026. With that weighing on Merck’s totals, Winrevair’s quarterly sales are the figure to watch when Merck reports its third quarter on October 29, 2026.

Is Too Much Of Your Wealth Riding On One Stock?

Most investors only saw Merck’s run after it had happened. When one position grows into a large part of your wealth, a sharp fall can hurt your whole plan, and selling to spread the money out can bring a large tax bill. Our partner advisory firm offers a free strategy review of ways to protect a concentrated position and unwind it with less tax.

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