TA896 · STA

Bulevirtide for treating chronic hepatitis D

Recommended with restrictionsMay 2023

Bulevirtide is recommended for treating chronic hepatitis D in adults with compensated liver disease only if there is evidence of significant fibrosis (METAVIR stage F2 or above or Ishak stage 3 or above) and their hepatitis has not responded to peginterferon alfa-2a (PEG-IFN) or they cannot have interferon-based therapy. Only recommended if the company provides it according to the commercial arrangement.

Source documents

Intervention

bulevirtide (Hepcludex)
· sodium taurocholate cotransporting polypeptide (NTCP) inhibitor · subcutaneous injection

Conditions

chronic hepatitis dgastroenterology · compensated_cirrhosis
chronic hepatitis dgastroenterology · chronic

Comparators

NameType Established Committee preferred
peginterferon alfa-2a (peg-ifn)active drugYes
standard care (symptomatic treatment, antivirals for hepatitis b)standard of careYes
standard carebest supportive careYes

Clinical trials

TrialDesignPhasePivotal
MYR 301RCT3Yes

Economic model

markov (company)
Time horizon: Lifetime
Cycle length: 24 weeks

ICER

£20,000–£30,000 (bulevirtide vs standard care) · high uncertainty

Methodological decisions (19)

baseline risk

Proportion of population with compensated cirrhosis at baseline

Company: 55% have compensated cirrhosis based on post-hoc analysis of MYR 301 fibrosis distributions

ERG: 47% have compensated cirrhosis based on primary MYR 301 data

Committee: Preferred baseline distribution based on MYR 301 primary data

ICER impact: uncertain_direction

baseline risk

Mean age at diagnosis for severity modifier calculation

Company: Use mean age from UKHSA cohort of people in UK with hepatitis D currently alive

ERG: Use alternative estimates from primary MYR 301 data

Committee: Preferred use of baseline mean age from full UKHSA dataset

ICER impact: uncertain_direction

comparator selection

MYR 301 included data from people not yet treated with interferon. Company positioned bulevirtide for post-PEG-IFN failure or contraindication population, but trial data included people with all scenarios.

Company: Most people in MYR 301 had already had IFN treatment; those who had not were likely to have contraindication or intolerance

ERG: Concerned that company evidence included people not relevant to specified decision problem

Committee: Accepted that response rates should reflect full trial population; accepted that evidence from full MYR 301 population was reasonable

ICER impact: uncertain_direction

model structure

Use of METAVIR fibrosis stages as health states in Markov model when population may be identified by transient elastography in clinical practice

Company: Presented Markov model with 10 health states based on METAVIR fibrosis stages F0-F4

ERG: Not explicitly stated but implied concern about mismatch between model structure and clinical practice

Committee: Noted that using METAVIR-based health states may not be appropriate if company positions bulevirtide in narrower population; would be acceptable if company amended positioning to cover entire marketing authorisation

ICER impact: uncertain_direction

model structure

Company used Markov model with METAVIR fibrosis staging (F0-F4 plus complications). Committee preferred elastography-based model due to narrow population positioning (F2+) not aligned with full marketing authorisation. Company maintained METAVIR approach at second meeting.

Company: Markov model using METAVIR staging appropriate; maintained this position despite committee preference

Committee: Elastography-based model preferred if bulevirtide positioned narrowly (F2+); METAVIR staging acceptable only if marketing authorisation expanded to full population

ICER impact: uncertain_direction

model structure

How to estimate fibrosis progression and hepatocellular carcinoma risk in hepatitis D

Company: Apply hazard ratios from publications comparing hepatitis D co-infected with hepatitis B to hepatitis B only, due to limited direct hepatitis D evidence

ERG: Use alternative sources of data that directly estimated natural history of disease in hepatitis D population

Committee: Preferred the EAG's approach to estimate natural history based on direct evidence in hepatitis D population

ICER impact: increases

mortality assumption

Natural history and disease progression modelling for hepatitis D. Company used hazard ratios comparing HDV+HBV to HBV-only due to limited HDV-specific data. EAG preferred direct HDV natural history sources. Committee concerned about systematic approach to literature validation.

Company: Applied hazard ratios from HDV+HBV vs HBV-only comparisons due to limited HDV-specific data and noted natural history of HDV not yet established; provided literature sources for compensation cirrhosis, HCC, liver-related mortality

ERG: Preferred alternative sources directly estimating natural history of disease in hepatitis D; could not validate company's data in model

Committee: EAG's approach preferred to estimate natural history in population of interest; company's approach lacked systematic methodology

ICER impact: uncertain_direction

other

Probability of hepatocellular carcinoma in combined responders

Company: Combined responders have lower risk of hepatocellular carcinoma

ERG: Combined responders have same risk as partial responders

Committee: Preferred company's assumption that clinical expert opinion supports lower risk for combined responders

ICER impact: decreases

other

When fibrosis regression can start after treatment initiation

Company: Not explicitly stated in company position

ERG: Fibrosis regression can only start from 96 weeks

Committee: Accepted EAG's assumption that fibrosis regression can only start from 96 weeks

ICER impact: increases

other

Application of 1.2 QALY weight for rare disease severity

Company: Weight of 1.2 should apply based on QALY shortfall calculations

ERG: Severity modifier did not apply according to EAG's preferred scenarios

Committee: Agreed 1.2 severity modifier should be applied; in all but 1 scenario QALY shortfall was over 12 QALYs

ICER impact: decreases

population generalisability

Baseline characteristics for UK population: age and proportion with cirrhosis at baseline. Company initially used Spaan et al. median age (35 years, 60% cirrhosis) but MYR 301 had baseline age 42 years with 47% cirrhosis.

Company: Updated base case to use median age (35 years) from UKHSA study; preferred to use age of people with hepatitis D currently alive (n=570)

ERG: Preferred mean age rather than median; preferred mean age from full UKHSA dataset of all people diagnosed with hepatitis D in UK (n=602)

Committee: Agreed mean age from full UKHSA dataset (n=602) was most appropriate measure of central tendency and bigger dataset

ICER impact: uncertain_direction

population generalisability

Fibrosis staging assessment method: METAVIR fibrosis staging via liver biopsy (invasive) vs. transient elastography/FibroScan (non-invasive)

Company: Used METAVIR staging (F2 or above) based on liver biopsy; later provided scenario analyses using transient elastography thresholds of 7.25 kPa and 8.0 kPa from external literature (Qi et al. 2018, EASL 2021)

ERG: Unable to validate EASL threshold; considered 8.0 kPa most validated threshold to rule out advanced fibrosis (F3+); unclear if company used systematic approach

Committee: Preferred non-invasive transient elastography assessment over invasive liver biopsy; noted high uncertainty about appropriate elastography threshold; accepted that in clinical practice fibrosis could be assessed by either transient elastography or biopsy

ICER impact: uncertain_direction

population generalisability

Baseline characteristics for NHS population: company used Spaan et al. (2020) retrospective UK analysis (n=107, age 35 years, 60% cirrhosis) vs MYR 301 trial (age 42 years, 47% cirrhosis). Committee preferred UKHSA data on mean age at diagnosis from full dataset (n=602) over median age estimate or cohort of currently alive patients (n=570).

Company: Used Spaan et al. baseline characteristics; later updated to median age (35 years) from UKHSA study; then updated to reflect currently alive HDV population (n=570)

ERG: Preferred mean age from full UKHSA dataset of people diagnosed with hepatitis D (n=602)

Committee: Mean age from full UKHSA dataset (n=602) is most appropriate as larger dataset and better reflects age at diagnosis

ICER impact: uncertain_direction

stopping rule

Treatment duration in model vs trial. Company assumed: combined responders indefinite; virological responders to week 72; non-responders to week 48. Trial allowed all to continue regardless of response. Committee preferred clinical assumptions based on expert input.

Company: Combined responders continue indefinitely; virological responders stop week 72; non-responders stop week 48. Later updated to combined responders with undetectable RNA stop week 100 (48+52), partial/non-responders stop week 72

ERG: Model duration mismatches trial protocol which allowed continued treatment regardless of response status

Committee: Combined responders likely continue but with some uncertainty; virological responders continuation uncertain; accepted week 72 stopping for partial/non-responders but acknowledged uncertainty remains

ICER impact: increases

treatment effect duration

Company extrapolated response beyond 48-week MYR 301 data to 72 weeks, assuming maintained response for all non-stopping patients. EAG preferred limiting to 48-week data. Committee noted trend of response loss over time despite some gaining response.

Company: Extrapolated response to 72 weeks; later clarified no extrapolation beyond 48 weeks as trend showed response increase during first 48 weeks

ERG: Limit response assessment to 48 weeks without extrapolation due to uncertainty in assumptions beyond trial data

Committee: Response limited to 48-week trial data; longer-term data would help but not yet available

ICER impact: decreases

treatment effect waning

Transition probabilities for fibrosis progression. Company assumed combined responders had zero progression and could regress (8.8% annual F4→F3, 13.3% annual F3→F2). Clinical experts and committee agreed responders still at some risk and regression rates seemed high. EAG assumed residual HCC risk in combined responders; company later assumed 20% of partial responder progression for combined responders.

Company: Combined responders: zero progression through fibrosis, 8.8% F4→F3 regression, 13.3% F3→F2 regression, no HCC risk. Later updated to 20% progression/HCC risk vs partial responders.

ERG: Combined responders should have residual HCC risk equal to partial responders, referencing Alfaiate et al. (2020)

Committee: Combined responders at risk of HCC; 20% of partial responder rates for progression/HCC acceptable and addressed uncertainties

ICER impact: increases

utility source

Health-state utility values from EQ-5D-3L in MYR 301 vs hepatitis B meta-analysis. Company argued EQ-5D lacked face validity for fibrosis differences and did not capture hepatitis symptoms. EAG and committee disagreed.

Company: EQ-5D-3L from MYR 301 lacks face validity; utility values from hepatitis B meta-analysis preferred

ERG: Impact of fibrosis on quality of life very small; EQ-5D appropriate; experts noted advanced liver disease often silent

Committee: Utilities based on MYR 301 EQ-5D-3L data appropriate

ICER impact: decreases

utility source

Source of health state utility values

Company: Utilities based on MYR 301 trial

ERG: Not explicitly differentiated

Committee: Committee concluded utilities based on MYR 301 were appropriate

ICER impact: negligible

utility value choice

Utility gain for combined responders was key cost-effectiveness driver. Company fitted Tobit regression to 48-week MYR 301 data using cirrhosis status and response at week 48. Committee concerned about lack of justification for Tobit approach and non-significance of resulting utility gain.

Company: Tobit regression appropriate due to ceiling effect (many at highest utility); utility gain plausible; later tested 50% and 75% reductions and incorporated maximum utility from prior hepatitis guidance

ERG: Preferred testing utility gain using lowest and highest values from previous NICE hepatitis B/C guidance rather than arbitrary 50%/75% reductions

Committee: Utility gain uncertain; preferred EAG's approach using maximum utility gain from previous hepatitis technology appraisals; accepted this in base case

ICER impact: increases

Evidence gaps

short follow upMYR 301 treatment period of 48 weeks is short; longer-term data needed to determine if response is sustained beyond 48 weeks
no direct comparisonMYR 301 did not include people from the UK; baseline characteristics assumed from Spaan et al. (2020) retrospective analysis of 107 UK patients
surrogate not validatedSurrogate outcomes of virological and biochemical response used; actual long-term complications (decompensated cirrhosis, hepatocellular carcinoma, death) not directly assessed as these take years to develop
no uk dataMYR 301 trial did not include people in the UK; baseline characteristics extrapolated from Spaan et al. retrospective analysis and UKHSA blood-borne virus testing data
short follow up48-week trial data on response; committee noted longer-term data would help resolve uncertainty about response maintenance beyond 48 weeks
short follow upTreatment duration and stopping rules not clearly defined in trial; unclear how long treatment should continue for virological responders and when to stop for non-responders
surrogate not validatedCombined virological and biochemical response endpoint; clinical experts noted detectable virus may remain even with combined response and risk of HCC not fully eradicated
short follow upClinical trial only published data for 48 weeks; uncertainty about response rates and treatment duration beyond 48 weeks
otherLimited evidence for hepatitis D natural history; modeling of disease progression not yet established in rare disease
no uk dataLimited UK-specific data on hepatitis D epidemiology; some data still being collected by UKHSA

Commercial arrangement

simple discount pas · confidential · critical for recommendation

Special considerations

End of life considered (not met) Severity modifier applied Innovation acknowledged Equality issues raised