New Medicines

Tezspire Severe, inadequately controlled asthma


New molecular entity

Development and Regulatory status

Phase III Clinical Trials
Pre-registration (Filed)
Mar 22Submission of evidence to NICE delayed until Q4 22 [26].
Jan 22Launched in the US with a list price of just under $48,000 a year [24]
Jan 22Tezepelumab is considered by analysts to have blockbuster potential [23].
Dec 21FDA has approved tezepelumab-ekko for the add-on maintenance treatment of adult and pediatric patients aged 12 years and older with severe asthma [22]
Jul 21Granted priority review in US [18]
Jul 21Filed in EU via centralised procedure [19].
May 21Amgen submit BLA for tezepelumab to FDA for treatment of patients with severe, uncontrolled asthma [16].
Dec 20Filings planned for 2021 [14].
Nov 19Filings based on NAVIGATOR data now expected in 2021 [12].
Sep 18Filings planned for 2020 or later [10].
Sep 18Awarded breakthrough therapy status in the US [9]
Feb 18PIII trials start [6].
Apr 12Amgen & AstraZeneca agreement to co-develop and co-promote tezepelumab worldwide [1].


Inhibitor of thymic stromal lymphopoietin (TSLP), an upstream mediator of inflammatory response
Asthma is a common illness, and accounts for around 60,000 hospital admissions and 200,000 bed days a year (2008 - 2012); it also caused 1,246 deaths (2012) including 21 children aged under 15 [4]. Expert view is that optimum management would reduce these rates, including two-thirds of deaths [5].
Severe, inadequately controlled asthma
Subcutaneous injection

Further information


Trial or other data

Mar 22PIII SOURCE RCT (n=150) found no significant improvement in oral corticosteroid dose reduction with Tezepelumab vs placebo, though in those with eosinophils >150/microL the difference was statistically significant (OR 2.58, 95%CI 1.16-5.75) [25].
Sep 21Sept 21: Amgen announces new data from PIII NAVIGATOR trial. The analysis evaluated effect in patients with or without reported nasal polyps (NP+ or NP-) in the past two years. The analysis showed tezepelumab achieved an 86% reduction in the annualized asthma exacerbation rate (AAER) in NP+ patients (95% CI: 70, 93) and 52% (95% CI: 42, 61) in NP− patients over 52 weeks, compared to placebo when added to standard of care (SoC) [20]
May 21PIII NAVIGATOR trial (n=1,061) is published in NEJM [17].
Mar 21PIII NAVIGATOR trial shows tezepelumab added to standard of care achieved a 56% reduction (p<0.001) in annual asthma exacerbation rate (AAER) over 52 weeks vs placebo. In subgroup analysis, pts with baseline eosinophil counts <300 cells per microliter, tezepelumab achieved reduction of 41% (p<0.001) in AAER. [15]
Dec 20PIII clinical trial (n=150) has failed to meet its primary outcome. Tezepelumab was unable to significantly reduce daily oral corticosteroid dose without loss of asthma control. Amgen states that failure to meet the primary endpoint may be due to study design. An earlier PIII trial showed tezepelumab significantly reduced asthma exacerbations, including patients with baseline eosinophil counts of <300 cells per microlitre. Amgen and AstraZeneca are continuing to prepare for filings in 2021 [14].
Nov 20AstraZeneca and Amgen announce that PIII trial NAVIGATOR (NCT03347279) trial has met its primary endpoint [13].
Jan 19First patient commences dosing in PIII DESTINATION extension study (NCT03706079). 975 patients will be recruited from the NAVIGATOR & SOURCE studies [11].
Jun 18First patient commences dosing in PIII 48-week SOURCE trial (NCT03406078) comparing tezepelumab in 140 patients recruited from 7 countries. Primary endpoint is reduction from baseline in daily OCS dose while not losing asthma control [8].
Nov 17Global PIII NAVIGATOR trial to evaluate the efficacy and safety of tezepelumab, in adults and adolescents with severe uncontrolled asthma starts (NCT03347279). Evaluation of the annualised asthma exacerbation rate is the defined primary endpoint of the trial. 1,060 patients in US and EU (including UK). Collection of primary outcome data should complete Sep 20 [7].
Sep 17AstraZeneca and Amgen announce promising results from the randomised, double-blind PIIb PATHWAY trial (NCT02054130). which recruited 955 patients with inadequately controlled, severe asthma to treatment with one of three doses of tezepelumab or placebo. Primary outcome was rate of asthma exacerbations at 52 weeks, and the results indicated relative reductions of 61%, 71% and 66% vs. placebo for the three doses. The drug was well tolerated [2,3].

Evidence based evaluations