The UK regulator has signed off GSK’s depemokimab, branded Exdensur, as an add‑on treatment for asthma in people aged 12+ and for adults with severe chronic rhinosinusitis with nasal polyps. It is the first biological medicine for these conditions given just twice a year in the UK. The MHRA confirmed approval on 15 December 2025.

Exdensur targets interleukin‑5 to dampen type 2 inflammation seen in eosinophilic disease. UK officials say it is administered as a subcutaneous injection once every six months; EMA documents add that it will come in pre‑filled pens or syringes, pointing to the potential for clinic or trained home use.

For GSK, this is a strategically important respiratory launch alongside existing asset Nucala. Nucala generated £1.784bn in 2024 sales, and analysts have long flagged depemokimab as a key growth driver into the late 2020s. Reuters has previously cited peak‑sales hopes around the multi‑billion‑pound mark, while recent brokerage notes point to meaningful 2026 contribution once major markets follow the UK.

Competition is strong but the dosing pattern is different. AstraZeneca’s Fasenra is given every four weeks for three doses then every eight weeks; Amgen/AstraZeneca’s Tezspire is monthly; GSK’s Nucala is monthly; Sanofi/Regeneron’s Dupixent for CRSwNP is typically every two weeks; and Roche/Novartis’s Xolair is dosed every two to four weeks based on IgE and weight. Exdensur reduces that to two injections a year.

NHS use will hinge on NICE. NICE has already opened an appraisal for depemokimab in severe eosinophilic asthma, scheduling publication for 25 March 2026. Until final guidance lands, broad NHS uptake is unlikely outside specialist funding routes. For CRSwNP, NICE’s latest published activity has focused on reviewing Dupixent, where a 2025 consultation draft did not recommend routine funding because of cost‑effectiveness uncertainties-useful context for how hard these appraisals can be.

Pricing is not public yet. As a yardstick, NICE lists Fasenra at £1,955 per pre‑filled syringe and Tezspire at £1,265 per dose before confidential discounts. NICE also notes these medicines are commissioned as high‑cost drugs and supplied under commercial arrangements. With only two Exdensur doses a year, administration costs and clinic capacity pressures could be lower-if list pricing and discounts land competitively.

Behind the decision is a solid dataset. GSK’s SWIFT‑1 and SWIFT‑2 asthma trials reduced annualised exacerbations over 52 weeks, and the ANCHOR programme in CRSwNP showed early and sustained improvements in polyp size and nasal obstruction with twice‑yearly dosing. These results underpinned regulatory filings across regions.

The approval is also the first anywhere for Exdensur, with momentum building in other markets. The EMA’s committee issued a positive opinion on 11–12 December 2025 and the U.S. FDA is due to decide by 16 December 2025. A clean read‑through from the UK could help, but each agency’s decision is independent.

For patients, the appeal is straightforward: fewer injections, potentially fewer hospital visits, and less disruption to work and study. Severe asthma affects around 200,000 people in the UK, and CRSwNP robs many of smell, sleep and day‑to‑day comfort-concerns reflected in patient testimony to NICE. A longer‑interval option could be easier to stick with over years of treatment.

Safety monitoring will be routine. The MHRA lists common side effects such as itchy skin, headache, tiredness and injection‑site reactions, and has encouraged reporting via the Yellow Card scheme. As with any new licence, the agency will keep effectiveness and safety under close review.

What this means for investors is measured rather than euphoric. Exdensur could shift share within GSK’s own IL‑5 franchise while taking aim at competitors that require 6–26 injections per year. The prize is meaningful if NICE guidance is favourable and if pricing aligns with NHS budgets; otherwise uptake will be slower and skewed to private or specialist centres.

Next checkpoints to watch: NICE’s asthma appraisal in March 2026, any UK commissioning decisions after guidance, and ex‑UK approvals following December’s CHMP opinion and the imminent U.S. PDUFA date. Those milestones will set the real trajectory for Exdensur volumes through 2026–27.