Nasdaq said on October 1 that Moderna will join the Nasdaq-100 before the open on October 9, replacing Warner Bros. Discovery.

  • Moderna was dropped from the same benchmark in late 2024 and is now re-entering after the sharp recovery in its share price.
  • MRNA shares gained massively after the company announced late-stage trial results of its cancer vaccine in combination with Merck’s Keytruda in August.
  • While the rally has helped Moderna regain its seat on the index, it has also raised valuation concerns.


Shares of Moderna (MRNA) rallied strongly on Monday, extending a year-long surge as investors positioned for the company’s return to the Nasdaq-100 later this week.

The stock traded around $204 in afternoon trading, up roughly 7% from Friday’s close of $190.01. The move put shares near a late-September high of $208.90 and left the company with a market value of about $82 billion. From a 52-week low near $22 last November, the shares are up more than fivefold in 2026.

MRNA’s Index Inclusion Spurs Rally

Nasdaq said on October 1 that Moderna will join the Nasdaq-100 before the open on October 9, replacing Warner Bros. Discovery. The media company is leaving because of its merger with Paramount Skydance, expected to close on October 6.

Inclusion does not change Moderna’s sales or pipeline, but it typically forces index funds to buy the stock around the effective date. Moderna was dropped from the same benchmark in late 2024 and is now re-entering after the sharp recovery in its share price.

Cancer Vaccine Still Driving The Moderna Story

The larger rerating began with the company’s personalized cancer vaccine, developed with Merck. In August, the partners said a late-stage trial of the vaccine in patients with high-risk melanoma that had been surgically removed met its main goal. The individualized mRNA shot, intismeran autogene, given with Merck’s immunotherapy Keytruda, delayed the return of disease and its spread compared with Keytruda alone.

The companies are also testing the approach in lung, kidney, and bladder cancer.

Citi Flags Valuation Concerns

While the rally has helped Moderna regain its seat on the index, it has also raised valuation concerns. In late September, Citi analyst Geoff Meacham downgraded Moderna to Sell from Neutral with a price target of $80, up from $60, citing valuation concerns for the downgrade. Meacham said Moderna’s market capitalization now stands close to Regeneron despite "materially lower expected revenue and earnings."

How Did MRNA Retail Traders React?

On Stocktwits, sentiment around MRNA rose from bearish to neutral territory over the past 24 hours, while message volume stayed at high levels.

Some Stocktwits users opined that Moderna is now overpriced.

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“Get ready to cover higher this friday when its included in the Nasdaq!,” another user wrote, pinning the rally on Monday to “forced buying” which will eventually push the stock up to $250.

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MRNA stock has gained 596% year-to-date. 

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