GSK stock heads into the open after a 4.6% jump on trial data

At the close on September 14, 2026, GSK stock gained 4.63% in London to 1,854.5 pence, outperforming the FTSE 100 as positive lung cancer trial data drove a session range between roughly 1,770 and 1,854 pence.

GSK stock closed at 1,854.5 pence on the London Stock Exchange on September 14, 2026, up 4.63% from the prior close and among the strongest risers in the FTSE 100 that day. According to UK market data cited by Yahoo Finance, the shares outperformed the broader index as investors reacted to new lung cancer trial results. Today, attention stays on the same oncology updates as the market opens, alongside key Bank of England and United Kingdom data later in the week that could influence sentiment toward large domestic stocks.

September 14, 2026 in numbers

GSK plc (ISIN GB0009252882, LSE: GSK) saw its London-listed shares climb to a close of 1,854.5 pence on September 14, 2026, after trading in a session range that reached a high around 1,837 pence and started from a prior close near 1,770.5 pence. As reported in a London market wrap by Yahoo Finance, GSK gained 4.63% at the close, markedly ahead of the FTSE 100, which was described as rising more modestly on the day. A separate London-closing summary from Morningstar highlighted GSK among the biggest FTSE 100 risers, noting an intraday move to 1,854.5 pence, reinforcing the scale of the stock's advance.

The session was driven by fresh oncology data. On September 14, 2026, GSK announced positive results for two lung cancer drugs, Jideytro and Ris-Rez, reporting strong outcomes in a ROS1-positive non small cell lung cancer setting and phase 3 overall survival data in China. As Reuters reported on September 14, 2026, pharma stocks rose 3.8%, with GSK gaining 4.7% after it announced positive results for the two lung cancer drugs, placing the company among the key supports for the index. A detailed biotech report from STAT on the same date described how GSK highlighted trial outcomes for both medicines, underscoring why the oncology news was a catalyst for the stock. The positive trial announcements gave GSK a clear edge over the wider FTSE 100, and the roughly 4.6% rise positioned the shares well above the prior close within their recent trading range.

Oncology focus and macro data today

Today, September 15, 2026, the market continues to digest the lung cancer trial updates that supported GSK's move in the last session, with investors watching how demand for the shares develops ahead of the open. The oncology data remain a central narrative for the company after the twin announcements on Jideytro and Ris-Rez described by Reuters, making further commentary on these programs and any follow-up communications potential drivers of trading volumes today. At the same time, the United Kingdom macro agenda is heavy this week, with labor market statistics, August inflation figures, producer price data and retail sales clustered around the Bank of England rate decision. As Yahoo Finance outlined, these data points and the upcoming central bank meeting shape sentiment across the FTSE 100, including large healthcare names such as GSK, because shifts in interest rate expectations can influence valuations of dividend-paying defensive stocks.