CHMP backs two AstraZeneca drugs: Klygefa in gMG, Enhertu in early breast cancer

On 21 September 2026, AstraZeneca announced that the CHMP issued two positive opinions recommending EU approval for separate medicines.

The first covers Klygefa (gefurulimab), developed by Alexion, AstraZeneca Rare Disease. The drug is recommended as an add-on to standard therapy for adults with generalised myasthenia gravis who test positive for anti-acetylcholine receptor antibodies.¹ If approved, the company said Klygefa would be the first and only dual-binding nanobody C5 inhibitor for this patient population.¹ The recommendation rests on the Phase III PREVAIL trial. Klygefa showed improvement from baseline in the Myasthenia Gravis Activities of Daily Living total score at week 26 versus placebo, with a treatment difference of -1.6 (95% CI: -2.4, -0.8, p<0.0001).¹ The company said the improvement was seen as early as week one and held through week 26, and safety was consistent with prior C5 inhibitors eculizumab and ravulizumab.¹ The trial enrolled 260 patients across 20 countries.¹ Klygefa is already approved in Japan and other countries, and regulatory filings based on PREVAIL are under review in the US, China and elsewhere.¹

The second opinion covers Enhertu (trastuzumab deruxtecan), jointly developed by AstraZeneca and Daiichi Sankyo. It is recommended as adjuvant monotherapy for adult patients with resected HER2-positive breast cancer who still have residual invasive disease after neoadjuvant taxane-based and HER2-targeted treatment.² In the DESTINY-Breast05 trial, Enhertu cut the risk of invasive disease recurrence or death by 53% versus trastuzumab emtansine (hazard ratio 0.47, 95% CI 0.34-0.66, p<0.0001), with 92.4% of Enhertu patients alive and disease-free at three years versus 83.7% on T-DM1.² The trial enrolled 1,635 patients across five continents.² Enhertu is already approved in the US and other countries for this same adjuvant use.²