Key Highlights

● Insmed reported third-quarter Revenue of $524.4 million versus the $499.5 million expected.

● Brinsupri generated $400.1 million in sales during the quarter.

● The low end of 2026 Brinsupri guidance rose to $1.35 billion.

● Health care was the best-performing S&P 500 sector on Thursday.

Insmed (NASDAQ:INSM) saw its new lung-disease drug blow past expectations in the third quarter, sending the biotech's shares sharply higher on a day health care led the market.

A launch that keeps outrunning forecasts

Insmed gave investors exactly what they wanted to hear before the opening bell on Thursday. The biotech reported third-quarter revenue of $524.4 million, comfortably ahead of the $499.5 million analysts expected and several times what it brought in a year earlier.

The engine was Brinsupri, its treatment for bronchiectasis, a chronic lung condition. The drug generated $400.1 million in sales during the quarter, up solidly from the second quarter. Chief executive Will Lewis said the U.S. launch "continues to exceed expectations."

The stock soared on October 29. Reports on the size of the gain differed depending on when they were taken: one outlet captured an especially steep jump in mid-morning trading, while two other sources reported somewhat smaller advances.

Guidance moves up again

Insmed also nudged its outlook higher. The company raised the low end of its 2026 Brinsupri guidance to $1.35 billion, while keeping the top end at $1.4 billion. Narrowing a range upward can signal a firmer view of the final quarter of the year.

For a company that only recently began selling the drug, the speed of the ramp is the story. Each quarter of upside shifts the conversation from whether Brinsupri can succeed commercially to how large it can eventually become.

Health care takes the lead

Insmed's surge fit neatly into the day's biggest theme. Health care was the best-performing sector in the S&P 500 on Thursday, powered by blockbuster results from Eli Lilly (NYSE:LLY), which closed at an all-time high after raising its revenue guidance, and Merck (NYSE:MRK), which beat estimates and lifted its profit outlook.

The pharma rally was part of a broader rotation away from mega-cap technology. Alphabet (NASDAQ:GOOGL) suffered its worst day since its 2004 IPO, dragging the Nasdaq Composite down 365.13 points to 26,184.72 and the Nasdaq-100 to 29,402.51. At the same time, more than 400 S&P 500 stocks rose and the Russell 2000 climbed 28.71 points to 2,859.22.

"Money is rotating within the market rather than leaving it," one market strategist said, according to market commentary.

Not every drugmaker shared in the glow. Alnylam (NASDAQ:ALNY) plunged after saying sales of its key TTR Franchise would likely land at the low end of guidance, a reminder that investors are punishing any sign of slowing Demand just as quickly as they are rewarding upside.

The macro picture

Thursday's data showed a hot economy. Third-quarter GDP grew faster than forecast and accelerated from the second quarter, while September PCE Inflation ran above the prior month's pace. The combination kept traders betting on another Federal Reserve rate hike in December, after the Central Bank held steady on Wednesday.

Health care stocks are often seen as defensive because demand for medicines does not depend heavily on the economic cycle, which helps explain why they attracted money on a choppy day.

What to watch

Insmed's next milestones are commercial. Investors will track whether Brinsupri can keep beating expectations in the fourth quarter and whether the company reaches the upper end of its $1.35 billion to $1.4 billion range for the year.

On the macro side, Friday brings the third-quarter Employment Cost index and Earnings from AbbVie (NYSE:ABBV), another big drugmaker whose results could test whether the sector's momentum holds. The Fed's December 8 to 9 meeting looms over everything, with a possible hike that could cool appetite for growth stocks.