AstraZeneca led the FTSE 100’s small group of gainers on Friday, climbing 0.68% to close at 13,834p even as the broader index slumped 2% on a combination of political uncertainty and global growth worries. The Cambridge-headquartered drugmaker, which trades under the ticker AZN, ended the session with a market capitalisation of £236.9 billion — making it once again Britain’s largest listed company by value.
Turnover in AstraZeneca shares reached 88,455 — modest by recent standards but enough to drive the index’s defensive corner. The session highlighted what fund managers increasingly describe as a “stockpicker’s market,” in which dispersion between winners and losers has widened sharply against a backdrop of macro and political volatility.
3I Group and the alternatives shine
Behind AstraZeneca, the day’s standout performer was 3I Group, which advanced 3.46% to 2,185p on volume of 389,923 shares. The private-equity-style investor, which holds significant exposure to European mid-market businesses through positions including Action and Audley Travel, closed the session valued at £27.5 billion. The shares have been one of the FTSE 100’s structural success stories of the past decade, despite a sharp recent pullback.
GSK rounded out the leading pharma names, finishing up 1.2% at 1,895p. The grouping of AstraZeneca, GSK, and the defensive consumer giant Diageo — which gained 1.17% — illustrated how investors are once again paying for earnings predictability in a market unsettled by the Iran war, the Hormuz oil disruption, and the Starmer leadership crisis.
The AI optimism crosses the Atlantic
One paradox of Friday’s session was that the FTSE’s decline came against a backdrop of fresh records on Wall Street. According to Sharecast News, “London’s stock market pushed higher for the second straight session on Thursday, helped by a calmer day on bond markets and a strong start on Wall Street, where a resurgence in AI positivity propelled US indices to new records.” That overnight tailwind did not survive into Friday’s London open.
Shell and Experian completed the top five FTSE 100 performers — Shell benefiting from continued strength in oil prices, Experian from steady demand for credit-data services even as consumer credit conditions tighten. Among the broader index, top constituents by market capitalisation now include HSBC at £311 billion, AstraZeneca at £289 billion, and Shell at £237 billion.
FTSE 250 underperforms
The picture in the FTSE 250, more domestically focused than its larger sibling, was less rosy. Mid-cap industrials and consumer-facing names were sold down as Sterling weakened to a one-month low against the dollar. The mid-cap index typically trades more closely with the perceived health of the UK domestic economy — and on that measure, the political risk premium is now visibly priced in.
The FTSE 100 itself remains up 1.04% over the past week and 20.25% over the past twelve months, despite the latest pullback. The all-time high of 10,934.94, reached on 27 February 2026, now looks distant. Whether the index can recover that level in 2026 depends, in roughly equal measure, on the Iran war’s resolution, on whether Sir Keir Starmer survives the summer, and on the durability of the AI rally that has done so much to support global equity multiples through a difficult macroeconomic year.
For long-term investors, however, the pharmaceutical leadership of recent sessions is a reminder of why the FTSE 100 has historically been more resilient than its critics suggest. With around 75% of constituent revenues earned overseas, a weaker pound is, paradoxically, often a tailwind. The challenge now is for that mathematical truth to outweigh the more visceral pull of domestic political headlines.
