Moderna’s shares surged 176 per cent after the company reported positive late-stage trial results for a personalized skin cancer vaccine, before falling more than 25 per cent the following day as investors appeared to take profits (20/08).

The experimental treatment, developed with Merck, combines Moderna’s mRNA-based vaccine with Merck’s Keytruda and showed that it could reduce the recurrence of melanoma and significantly extend the time patients lived without their melanoma returning.

The results sent Moderna’s market value to $69.6bn on Wednesday after its shares gained 177 per cent in New York, adding $44bn to its market capitalisation.

Moderna Skin Cancer Vaccine Shows Positive Trial Results

The experimental treatment is designed as a custom-made vaccine for each patient, based on the specific characteristics of their tumour.

Moderna and Merck said the treatment was the “first and only” combined therapy to show “statistically significant and clinically meaningful improvements” in preventing melanoma from redeveloping and spreading in patients whose melanomas had been removed.

“Today’s results represent a landmark moment for adjuvant melanoma treatment,” said Professor Georgina Long, the study’s principal investigator and medical director of Melanoma Institute Australia.

Analysts expect the treatment to receive US regulatory approval next year.

Personalized mRNA Treatment Targets Melanoma

The cancer shot would be given to patients who have already been diagnosed with melanoma and is designed specifically to attack their tumour.

Moderna has been a leader in messenger RNA technology, or mRNA, which teaches the body’s immune system to identify and attack illnesses such as Covid-19.

The company is seeking to develop the experimental vaccine technology for different types and stages of cancer and has described the results as an important milestone towards vaccinating patients with the disease.

“We have started to demonstrate the potential of an entirely new class of medicine — and an entirely new way of thinking about cancer care: using the information encoded within an individual patient’s cancer to design a specific therapy that helps train their immune system to fight it,” Stéphane Bancel, Moderna’s chief executive, wrote in a blog post on Wednesday.

Moderna and Merck have said they are looking into several trials of the vaccine for other cancers, including non-small-cell lung cancer and bladder cancer.

Moderna Stock Falls After Record Surge

Moderna shares plunged more than 25 per cent to around $129 by early Thursday afternoon, following the record-setting 176 per cent increase on Wednesday that pushed the stock above $174.

The decline reduced Moderna’s market valuation to $51.5bn, more than $18bn below its $69.6bn valuation at Wednesday’s close.

The fall came as investors appeared to pull back after the sharp increase in the company’s share price.

Wall Street analysts continued to praise the trial results. Bank of America analyst Alec Stranahan raised his price target for Moderna to $170 from $40 and called the results a “watershed moment” for the company, allowing it to further diversify from infectious disease.

Stranahan noted that it was still not known how much better Moderna’s combined drug was than Keytruda alone and said more testing would likely be necessary.

Cancer Vaccine Central to Moderna’s Business

Moderna’s business grew rapidly from the success of its mRNA-based Covid-19 vaccine, but the company has since faced weaker demand for the jab.

Last year, Moderna became the most shorted stock in the S&P 500. The company has been betting on new cancer vaccines to drive a turnaround and has worked with Merck on the vaccine for years.

Even after Wednesday’s sharp rise, Moderna’s shares remained below one-third of their 2021 peak, reached after the company launched its Covid vaccine.

Moderna has also been building manufacturing capacity to prepare for additional vaccine production, including the purchase of a new facility in Massachusetts in 2023.

This article is a summary of two original articles. The full versions can be read at the following links:

https://www.ft.com/content/a98a77e2-5156-4189-b971-974a7e60130f?syn-25a6b1a6=1

https://www.forbes.com/sites/tylerroush/2026/08/20/moderna-stock-plunges-25-wiping-out-18-billion-after-historic-cancer-vaccine-breakthrough/

PHOTO: STAT/ALEX HOGAN

This article was created with AI assistance.

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