TA880 · STA

Tezepelumab for treating severe asthma

Recommended with restrictionsNot stated

Recommended in routine commissioning for treating severe asthma in people 12 years and over, when treatment with high-dose inhaled corticosteroids plus another maintenance treatment has not worked well enough. Only if: people have had 3 or more exacerbations in the previous year or are having maintenance oral corticosteroids, and the company provides tezepelumab according to the commercial arrangement.

Source documents

Intervention

tezepelumab (Tezspire)
Biological · TSLP (thymic stromal lymphopoietin) antagonist · not stated in this section

Condition

severe asthmarespiratory · chronic

Comparators

NameType Established Committee preferred
standard care (high-dose inhaled corticosteroids plus another maintenance treatment)standard of careYes
standard care plus add-on biological treatmentsactive drugYes
placeboplacebo
omalizumabactive drugYes
reslizumabactive drugYes
benralizumabactive drugYes
mepolizumabactive drugYes
dupilumabactive drugYes
standard care alonestandard of careYes
standard carestandard of careYes

Clinical trials

TrialDesignPhasePivotal
PATHWAYRCTPhase 3Yes
NAVIGATORRCTPhase 3Yes
SOURCERCTPhase 3Yes

Economic model

markov (company)
Time horizon: not stated in this section
Cycle length: 4-weekly

Methodological decisions (16)

comparator selection

Selection of appropriate comparators for tezepelumab. Committee agreed that standard care (high-dose inhaled corticosteroids plus another maintenance treatment) with or without add-on biological treatments are relevant comparators.

Committee: Standard care with or without add-on biological treatments

ICER impact: negligible

indirect comparison method

Company used network meta-analysis (NMA) to compare tezepelumab with biological treatments. NMAs had considerable uncertainty due to unresolvable limitations in evidence and mismatch between trial biomarkers and NICE-recommended treatment biomarkers.

Company: NMAs provided robust comparisons; company updated NMA inputs to address concerns and provided scenarios based on simulated treatment comparison and published NMAs

ERG: Original and updated NMAs both had considerable uncertainty; biomarker evidence in trials did not all match biomarkers used for NICE-recommended treatments

Committee: Tezepelumab is likely to have similar clinical effectiveness compared with existing biological treatments, but this was highly uncertain

ICER impact: uncertain_direction

indirect comparison method

Subgroup selection for NMA comparisons: baseline blood eosinophil count thresholds

Company: Used subgroup with baseline blood eosinophil count at least 300 cells per microlitre for reslizumab, mepolizumab, benralizumab

ERG: Preferred subgroup with baseline blood eosinophil count at least 150 cells per microlitre for dupilumab comparison

Committee: Company's updated NMA using ≥300 cells/µL for reslizumab/mepolizumab/benralizumab; EAG's preferred ≥150 cells/µL for dupilumab

ICER impact: uncertain_direction

model structure

Company used 5-state Markov model with health states: controlled asthma, uncontrolled asthma, uncontrolled asthma with exacerbation, controlled asthma with exacerbation, and dead

Company: 5-state model is appropriate

ERG: Model structure appropriate but uncertain about approach of modelling exacerbations as controlled and uncontrolled

Committee: Model structure is appropriate for decision making

ICER impact: negligible

model structure

Company's approach of modelling asthma exacerbations in controlled and uncontrolled states; model prohibited transitions from controlled asthma to uncontrolled asthma with exacerbation and from uncontrolled asthma to controlled asthma with exacerbation

Company: Approach is appropriate; distinguishing between exacerbations in previously controlled asthma from asthma not previously controlled captures differences in health-related quality of life, costs and mortality

ERG: Considered it inappropriate; transition probabilities from exacerbation health states to controlled asthma state may have been overestimated; clinical opinion suggested people can have exacerbations in any health state with different risk depending on starting health state

Committee: Company's approach is acceptable for decision making

ICER impact: increases

mortality assumption

Asthma-related mortality estimates in model; company originally assumed deaths from asthma could only occur through exacerbations; company later provided UK-based real-world study from CPRD

Company: Original asthma-related mortality estimates were appropriate; later provided CPRD analysis showing all-cause mortality for people with severe asthma was substantially higher than predicted

ERG: Originally considered company's probabilities overestimated asthma-related mortality for people younger than 75 years; re-estimated based on 2020 ONS mortality data; later acknowledged CPRD analysis was well done and reduced uncertainty but had limitations in applicability

Committee: Company's original base-case asthma-related mortality estimates were more appropriate but CPRD analysis was informative for non-biological eligible group; will consider cost-effectiveness scenarios using both estimates

ICER impact: increases

mortality assumption

Asthma-related mortality estimates for people younger than 75 years

Company: Deaths from asthma only through exacerbations; original base-case estimates

ERG: EAG re-estimated using 2020 Office of National Statistics mortality data, resulting in lower probability (0.001 per 4-weekly cycle)

Committee: Company's original base-case asthma-related mortality estimates more appropriate, but CPRD analysis informative for non-biological eligible group; consider both scenarios

ICER impact: decreases

mortality assumption

Application of real-world CPRD mortality data across all subgroups vs only non-biological eligible subgroup

Company: Applied CPRD-based all-cause mortality results across all subgroups

ERG: Should apply overall population estimates across all subgroups or estimate and apply mortality rates by subgroup individually; multiplier used was uncertain due to limited sample size; calibrating exacerbation-related mortality to all-cause mortality may have overestimated

Committee: Will consider cost-effectiveness scenarios using both original base-case asthma-related mortality estimates and CPRD data (only in non-biological eligible subgroup)

ICER impact: decreases

other

Definition of clinical response to tezepelumab for ongoing treatment continuation. Company initially proposed any reduction in exacerbations or oral corticosteroids dose. EAG considered this inappropriate and proposed 20-50% reduction. Committee and stakeholders (supported by clinical opinion from severe asthma specialists) agreed on updated definition: 50% reduction in exacerbations for people not on maintenance oral corticosteroids; 50% reduction in oral corticosteroid dose for those on maintenance therapy.

Company: Any reduction in exacerbations or oral corticosteroids dose constitutes treatment response

ERG: 20-50% reduction in exacerbations is appropriate treatment response

Committee: 50% reduction in exacerbations (for people not on oral corticosteroids) or 50% reduction in oral corticosteroid dose (for those on maintenance therapy)

ICER impact: uncertain_direction

other

ACQ-6 cut-off score to define asthma control status in model

Company: Using ACQ-6 cut-off score of 1.5 to define asthma control (controlled <1.5, uncontrolled >1.5); company considered using partially controlled asthma as third health state but did not implement due to multiple subgroups being considered

ERG: Preferred using cut-off of 1 based on Juniper et al. (2006) study suggesting crossover point close to ACQ-6 score of 1; considered cut-off of 1.5 would misclassify some asthma and overestimate treatment effectiveness

Committee: Using ACQ-6 score of 1.5 as cut-off is appropriate; clinical expert agreed with company's approach

ICER impact: negligible

other

Definition of responder to treatment (only those who respond continue in model)

Company: Company proposed responder definition

Committee: Company's updated treatment response definition acceptable

ICER impact: not specified

population generalisability

Whether trial populations (PATHWAY, NAVIGATOR, SOURCE) are representative of NHS patients with severe asthma. Clinical experts and EAG noted well-balanced baseline characteristics and considered populations reflective of NHS severe asthma patients.

Committee: Trial populations are generally representative of NHS patients

ICER impact: negligible

stopping rule

Company included one-off stopping at 52 weeks in model; after 52 weeks, different transition probabilities applied for people whose asthma was considered to have responded

Company: Approach reflects stopping rules in previous NICE technology appraisals for other add-on biological treatments; appropriate to have different transition probabilities for responders after 52 weeks

ERG: Overestimated treatment effect because stopping had been accounted for; set transition probabilities before and after 52 weeks to be equal as conservative approach due to lack of data

Committee: Company's approach is acceptable

ICER impact: increases

treatment effect duration

Duration and magnitude of exacerbation reduction/maintenance oral corticosteroid dose reduction

Company: Not explicitly stated

Committee: 50% reduction in exacerbations for those without maintenance oral corticosteroids; 50% reduction in oral corticosteroid dose for those on maintenance

ICER impact: not specified

utility source

Additional utility increment for people receiving biological treatments beyond health state utilities

Company: Applied utility gain not associated with health state; based on EQ-5D-5L regression analysis from tezepelumab trials; aligned with benralizumab and omalizumab precedent

ERG: Effectiveness should be reflected in modelled health states; adding additional utility increment with borderline statistical significance inappropriate; in benralizumab/omalizumab precedent, biological treatment utilities were attached to health states

Committee: Company's updated approach appropriate after removing non-significant biological-specific utility gain

ICER impact: decreases

utility value choice

Company assumed utility increment for people who had a biological treatment, not associated with any health state in model

Company: Utility increment applied because benefits of treatment were not captured by model health states

ERG: Not explicitly stated in chunk

Committee: Committee questioned face validity; company explained approach

ICER impact: increases

Evidence gaps

no direct comparisonNo direct head-to-head comparison with other biological treatments. Indirect comparison with other biological treatments (anti-IL-5 inhibitors, dupilumab, omalizumab) suggests similar clinical effectiveness but with uncertainty.
short follow upTrial follow-up periods are 48-52 weeks; longer-term follow-up data not provided in this chunk.
no uk dataOnly NAVIGATOR trial included UK participants; PATHWAY and SOURCE were conducted globally but did not specifically report UK data.
no direct comparisonNo direct comparison between tezepelumab and existing biological treatments including omalizumab, reslizumab, benralizumab, mepolizumab and dupilumab
otherBiomarker evidence in the trials did not all match the biomarkers used for NICE-recommended treatments; challenges in matching exact subgroup data because of lack of evidence
no direct comparisonNMA used for comparisons with other biological treatments; indirect evidence with uncertainties
surrogate not validatedModel structure limited to controlled/uncontrolled asthma; partially controlled state considered but not implemented

Commercial arrangement

simple discount pas · confidential · critical for recommendation

Special considerations

Innovation acknowledged Equality issues raised

Cross-references

comparator guidance — NICE's technology appraisal guidance on benralizumab regarding utility gains with biological treatments
same condition — NICE's technology appraisal guidance on benralizumab for asthma mortality estimation