3 The manufacturer's submission
The Appraisal Committee (appendix A) considered evidence submitted by the manufacturer of tocilizumab, a review of this submission by the Evidence Review Group (ERG; appendix B), and two additional analyses by the Decision Support Unit (DSU; appendix B).
Clinical effectiveness
3.1
In the submission, the manufacturer presented evidence on the clinical effectiveness of tocilizumab in combination with DMARDs for two populations: people whose rheumatoid arthritis had responded inadequately to previous DMARDs but before treatment with a TNF‑alpha inhibitor (the 'DMARD‑IR' population) and people whose rheumatoid arthritis had responded inadequately to previous TNF‑alpha inhibitors but before treatment with rituximab (the 'TNF‑IR' population). The manufacturer also presented evidence on the clinical effectiveness of tocilizumab as monotherapy. The submission focused on the tocilizumab 8 mg/kg treatment arms of the included studies because this is the recommended dose in the SPC. Some of the studies also included doses other than the licensed dose. Results for doses other than the licensed dose are not considered in this appraisal.
Tocilizumab plus methotrexate as a treatment option after an inadequate response to conventional DMARDs
3.2
The main clinical-effectiveness evidence for the DMARD‑IR population came from three randomised controlled trials (RCTs). All three RCTs were double-blind, placebo-controlled parallel-group studies in adults with moderate to severe active rheumatoid arthritis whose condition had responded inadequately to treatment with methotrexate (OPTION and LITHE) or traditional DMARDs (TOWARD). The OPTION trial assessed the effects of tocilizumab 8 mg/kg plus methotrexate (n=205) compared with placebo plus methotrexate (n=204). The LITHE trial assessed the effects of tocilizumab 8 mg/kg plus methotrexate (n=398) compared with placebo plus methotrexate (n=393). The TOWARD trial assessed the effects of tocilizumab 8 mg/kg plus DMARDs (n=805) compared with placebo plus DMARDs (n=415).
3.3
The primary outcome in the RCTs was the proportion of people with an American of Rheumatology (ACR) 20 response at week 24. This was defined as at least a 20% improvement in both the tender joint count and the swollen joint count and at least a 20% improvement in three of the other five core set measures included in the ACR score. In all three RCTs, the same outcome measure and data collection instruments were used. The manufacturer stated that the RCTs had similar patient populations. This was demonstrated by general demographics and the effect of various factors on the ACR20 response rate, which was examined by logistic regression analysis. No statistically significant differences were found in treatment effects between studies and the manufacturer inferred that pooling the results of the three RCTs for the primary outcome was appropriate. The manufacturer's submission stated that the adjusted odds ratio for the ACR20 response of tocilizumab 8 mg/kg plus DMARD compared with placebo plus DMARD was approximately 4.2. Averaged ACR20 response rates, described as pooled results, were 59.2% in the tocilizumab 8‑mg/kg arm compared with 25.8% in the placebo arm (p≤0.0001) at week 24.
3.4
Secondary outcomes of the RCTs, measured at 24 weeks, were pooled across the three RCTs by the manufacturer. Pooled ACR response rates were: 37.0% compared with 9.6% for ACR50 response rates (p<0.0001), 18.5% compared with 2.4% for ACR70 response rates (p≤0.0001), and 4.2% compared with 0.3% for ACR90 response rates (p≤0.0001), for the tocilizumab 8‑mg/kg plus DMARD arms and placebo plus DMARD arms respectively. The manufacturer also presented averaged disease activity score 28 (DAS28) results from the three RCTs. Approximately half of all people in the RCTs reached low disease activity, defined as DAS28 of less than 3.2. Approximately one-third of people in the RCTs went into remission, defined as DAS28 of less than 2.6. The proportion of participants going into remission while on tocilizumab was reported to increase during the study period. There was a greater decrease (improvement) in averaged health assessment questionnaire (HAQ) results from baseline HAQ score in the tocilizumab groups than in the placebo groups. In the pooled population at week 24, the proportion of participants with a clinically relevant improvement in HAQ (defined as a decrease of at least 0.25 in an individual's total score) was higher in the tocilizumab groups (68%) than in the placebo groups (52%).
3.5
Additionally, European quality of life (EuroQoL) health-state questionnaire (EQ‑5D) scores were collected in the OPTION and LITHE RCTs. In the OPTION RCT, the baseline mean EQ‑5D was 0.393 (standard deviation 0.327) in the tocilizumab 8 mg/kg plus methotrexate arm, and 0.391 (standard deviation 0.329) in the placebo plus methotrexate arm. At follow-up, the mean EQ‑5D was 0.671 (standard deviation 0.237) in the tocilizumab 8 mg/kg arm and 0.534 (standard deviation 0.318) in the placebo arm. The manufacturer did not provide EQ‑5D results from the LITHE RCT separately by treatment arm.
3.6
Two single-arm extension studies assessed maintenance of clinical benefit of tocilizumab beyond 24 weeks. Overall, response rates for those remaining on tocilizumab plus DMARD treatment were maintained or continued to improve with duration of treatment, with an increasing proportion of people achieving higher ACR scores over time. The manufacturer reported that improvements in HAQ scores were observed for up to 132 weeks in the pooled tocilizumab 8 mg/kg plus DMARD arm.
3.7
No head-to-head studies were identified that provided evidence on the clinical effectiveness of tocilizumab compared with TNF‑alpha inhibitors and abatacept for the DMARD‑IR population. Therefore, the manufacturer conducted a mixed treatment comparison. A total of 18 RCTs (including OPTION, LITHE and TOWARD) were identified for inclusion. All studies were randomised, placebo-controlled, double-blind trials and all had a follow-up period of either 24 or 30 weeks. Participants were predominantly female (approximately 80%), older than 50 years, had experienced more than 6 years' duration of rheumatoid arthritis, were previously treated with an average of two or more DMARDs, and more than half had used non-steroidal anti-inflammatory drugs or glucocorticoids concomitantly. The manufacturer reported that the baseline characteristics across the trials were comparable to ACR core parameters. Results for TNF‑alpha inhibitors were pooled, because it was assumed there was no difference in efficacy between these drugs. This assumption was reported to be informed by the guidance on adalimumab, etanercept and infliximab for rheumatoid arthritis (NICE technology appraisal guidance 130).
3.8
The mixed treatment comparison suggested that tocilizumab showed efficacy (measured by ACR20 and ACR50 response rates) comparable to all included biological treatments. For the ACR70 response rate, tocilizumab treatment was associated with a higher response rate than the TNF‑alpha inhibitors and abatacept (relative risks of 1.77 and 1.98 respectively). In the base-case comparison, there was a greater than 99% probability that tocilizumab was more efficacious than biological treatments (that is, etanercept, infliximab and adalimumab), as measured by ACR70 response rates. The manufacturer stated that homogeneity at each ACR response level was assessed using Cochran's Q‑statistic (ACR20: 44.1857, p=0.0002; ACR50: 41.6878, p=0.0004; ACR70: 25.5752, p=0.0603). Based on these results, the manufacturer used random-effects methods to estimate ACR20 and ACR50 response rates, and fixed-effect methods to estimate ACR70 response rates. As well as the base-case mixed treatment comparison, the manufacturer also presented three scenario analyses, which included or excluded data from certain trials included in the base case. The manufacturer stated that overall the results from these alternative scenarios were consistent with the initial findings.
Tocilizumab plus methotrexate as a treatment option after an inadequate response to a TNF‑alpha inhibitor
3.9
The main clinical-effectiveness evidence for the TNF‑IR population came from one RCT, known as RADIATE. RADIATE was a double-blind, placebo-controlled, parallel-group study in adults with moderate to severe rheumatoid arthritis. The participants' rheumatoid arthritis had responded inadequately to previous TNF‑alpha inhibitor therapy. RADIATE assessed the effects of tocilizumab 8 mg/kg plus methotrexate (n=170) compared with placebo plus methotrexate (n=158).
3.10
The primary outcome of the RADIATE trial was ACR20 response rate. At 24 weeks, 50% of people in the tocilizumab arm compared with 10% of people in the placebo arm had experienced an ACR20 response (p<0.0001). Additionally, at 24 weeks, 28.8% compared with 3.8% had experienced an ACR50 response (p<0.0001), and 12.4% compared with 1.3% had experienced an ACR70 response (p<0.0002), for the tocilizumab arm and the placebo arm respectively. At week 24, the mean change from baseline in DAS28 was -3.16 for tocilizumab and -0.95 for placebo. The manufacturer stated that the remission rates were similar to those seen in the DMARD-IR population at 24 weeks. The mean decrease in HAQ from baseline at 24 weeks for the tocilizumab group was 0.39, compared with 0.05 for the placebo group.
3.11
Two single-arm extension studies assessed the maintenance of clinical benefit of tocilizumab plus DMARDs beyond 24 weeks. Response rates to therapy with tocilizumab were maintained or continued to improve with duration of treatment (as in the DMARD‑IR population). Results similar to those for the DMARD‑IR population were reported and the manufacturer noted that the pattern of improvement in mean HAQ score was also observed for up to 132 weeks.
Tocilizumab as a monotherapy
3.12
One RCT (AMBITION) assessed the effects of tocilizumab 8 mg/kg alone (n=288) compared with methotrexate alone (n=284). This was a double-blind, placebo-controlled trial that included a sub-study tocilizumab arm in which placebo was given first for 8 weeks and then tocilizumab was given for 16 weeks. Most of the people in the AMBITION RCT had not received treatment with methotrexate before or had stopped methotrexate treatment for reasons other than toxicity or lack of efficacy.
3.13
The ACR20 response rate at 24 weeks in the intention-to-treat population was 69.9% in the tocilizumab arm compared with 52.5% in the methotrexate arm. The weighted difference in ACR20 response was 0.19 (95% confidence interval 0.11 to 0.27). The manufacturer concluded that treatment with tocilizumab was non-inferior to treatment with methotrexate. The manufacturer also stated that the trial population of AMBITION was not in accordance with the SPC of tocilizumab. This was because the AMBITION trial had recruited people who had not received any previous treatment with methotrexate; the SPC states that tocilizumab can be given as monotherapy in case of intolerance to methotrexate or if continued treatment with methotrexate is inappropriate.
Adverse events
3.14
The manufacturer reported that adverse events associated with the mechanism of IL‑6 receptor (IL‑6R) inhibition were observed in all tocilizumab treatment groups. These adverse events included transient hepatic transaminase elevations, asymptomatic elevations of indirect bilirubin, transient neutropenia, and lipid elevations that appear to occur in association with marked decreases in acute phase proteins. In addition, serious infections associated with the immunomodulatory effects of tocilizumab were comparable with the incidence of serious infections with TNF-alpha inhibitors. Adverse events reported more frequently with tocilizumab 8 mg/kg monotherapy than in the methotrexate group were abdominal pain and discomfort, headache, dizziness, rash, pruritis and elevated blood pressure, neutropenia, leukopenia and hyperlipidaemia. Most of these events were mild and transient. The manufacturer reported that there was no increase in the severity or frequency of adverse events with prolonged exposure to the tocilizumab 8 mg/kg dose.
Follow-up data
3.15
In addition to the original submission, the manufacturer of tocilizumab provided updated data with a maximum of 180 weeks of follow-up. The response rates of all people who received at least one dose of tocilizumab in the OPTION, AMBITION, RADIATE and TOWARD trials were analysed. A total of 3986 people were included in the long-term analyses. Approximately 14% of people discontinued tocilizumab treatment for safety reasons (including intercurrent illness). The manufacturer stated that tocilizumab increased or maintained ACR response rates in the DMARD‑IR, TNF-IR and tocilizumab monotherapy populations. This was demonstrated by the increased proportion of people with ACR50 and ACR70 responses and with an ACR70 response maintained for 24 consecutive weeks. The manufacturer also used the long-term follow-up data to re-estimate the HAQ progression with tocilizumab. The manufacturer stated that there was a negative trend (an improvement) in HAQ progression for both the DMARD‑IR and TNF‑IR populations.
Cost effectiveness
3.16
The manufacturer did not identify any economic evaluations of tocilizumab and developed an economic model for the submission. This was an individual sampling model with a hypothetical homogenous cohort. The model used a lifetime horizon for costs and benefits. It considered the DMARD‑IR and TNF‑IR populations separately. No evidence on the cost effectiveness of tocilizumab monotherapy was presented.
3.17
The manufacturer's initial economic model compared a treatment sequence that included tocilizumab with the same treatment sequence without tocilizumab for two populations. For the DMARD‑IR population, tocilizumab plus methotrexate was the first biological treatment and if the condition did not respond or if the ACR20 response rate was no longer achieved then etanercept plus methotrexate was the next treatment. This was followed by rituximab plus methotrexate, then leflunomide, then gold, then ciclosporin until people withdrew from the last treatment (ciclosporin) and moved on to palliative care. The sequence was the same for the comparator arm, but excluded tocilizumab plus methotrexate at the beginning. For the TNF‑IR population, the sequence was the same as the DMARD‑IR population, except for the omission of etanercept plus methotrexate (that is, the first treatment in the comparator arm was rituximab plus methotrexate).
3.18
The probabilities of response were derived from the adjusted ACR response rates (adjusted for placebo differences across trials) from the base-case mixed treatment comparison. There were four categories of response: non-response, ACR20 response, ACR50 response, and ACR70 response. People were assigned a predefined drop in HAQ score (that is, an improvement in physical function) based on their ACR responses. Data from four RCTs (OPTION, TOWARD, LITHE and RADIATE) were analysed to estimate the relationship between ACR response and HAQ score in the first 24 weeks. People whose condition responded were assumed to have a constant probability of withdrawal owing to lack of efficacy. The probability of withdrawing from treatment was the same for the biological treatments (infliximab, etanercept, adalimumab, rituximab and tocilizumab) and was calculated as the average of two withdrawal rate estimates for etanercept and infliximab. At the point of switching to the next treatment, people were assumed to experience an increase in their HAQ score (rebound) equal to the initial HAQ improvement. After the initial 24‑week period the HAQ score with tocilizumab plus methotrexate was assumed to decrease linearly (improve) based on the observational extensions to the RCTs. Because of substantial uncertainty in the data for weeks 132–156, this continued improvement was only assumed for the first 3 years in the DMARD-IR cohort and 2.5 years in the TNF-IR cohort. Beyond this (3 years after initial treatment in the DMARD-IR cohort and 2.5 years after initial treatment in the TNF-IR cohort), the HAQ score was assumed to stay constant (that is, zero HAQ improvement) with tocilizumab plus methotrexate treatment. After the initial 24‑week treatment period, no change in HAQ score was assumed (zero HAQ improvement) for biological treatments such as etanercept and rituximab. After the initial 24‑week treatment period, an increase in HAQ score (that is, a worsening of physical function) was assumed for traditional DMARDs. The manufacturer also carried out sensitivity analyses using an assumption of zero HAQ progression (no improvement or worsening) while on treatment.
3.19
Tocilizumab plus methotrexate was assumed to be given for a minimum of 6 months and the administration cost of each infusion of tocilizumab was assumed to be £142 (see section 3.25 for subsequent considerations of administration costs). The costs of treating any adverse events were not included in the economic model presented by the manufacturer. The manufacturer reported that EQ‑5D scores from the tocilizumab OPTION and LITHE trials were mapped to HAQ scores using a quadratic regression model. Alternative mapping equations as used in the guidance on adalimumab, etanercept and infliximab for rheumatoid arthritis (NICE technology appraisal guidance 130) and other submissions to NICE were examined in scenario analyses. Utility weights were derived from the EQ‑5D scores using the UK time trade-off tariff. Adverse events associated with tocilizumab treatment were assumed to generate an insignificant burden on people's quality of life, and therefore were not included in the model.
3.20
For the DMARD‑IR population, the treatment sequence including tocilizumab plus methotrexate compared with the sequence without tocilizumab produced incremental costs of £23,253 and incremental quality-adjusted life years (QALYs) of 1.17. This resulted in a base-case incremental cost-effectiveness ratio (ICER) of £19,870 per QALY gained. For the TNF‑IR population, the treatment sequence including tocilizumab plus methotrexate compared with the sequence without tocilizumab produced incremental costs of £26,640 and incremental QALYs of 1.21. This resulted in a base-case ICER of £22,003 per QALY gained. Probabilistic sensitivity analyses suggested that the addition of tocilizumab and methotrexate to the treatment sequences had a 56.4% and 22.4% probability of being cost effective (for the DMARD‑IR and TNF‑IR populations respectively) if the maximum acceptable amount to pay for a QALY gained is £20,000. All scenario analyses presented by the manufacturer resulted in ICERs of less than £30,000 per QALY gained. The ICERs increased to £24,905 and £24,739 per QALY gained for the DMARD‑IR and TNF‑IR populations respectively, using an assumption of no change in HAQ score (that is, no continued improvement on tocilizumab after the initial ACR response).
Manufacturer's response to consultation
3.28
In response to three rounds of consultation for the original guidance on tocilizumab for rheumatoid arthritis (NICE technology appraisal guidance 198), the manufacturer presented revised ICERs for the DMARD‑IR and TNF‑IR populations incorporating some of the ERG's suggested changes. The manufacturer also provided ICERs for positioning tocilizumab after an inadequate response to rituximab, and tocilizumab for people who are intolerant to rituximab or for whom rituximab is contraindicated. The clinical-effectiveness data for tocilizumab used in these positions were taken from the RADIATE trial. All of the revised and new ICERs incorporated degraded ACR response rates for tocilizumab, etanercept and rituximab when they are used later in the treatment sequence. Estimates for etanercept were based on treatment response to a second or third TNF‑alpha inhibitor reported from the South Swedish Arthritis Treatment Group. These downgraded the efficacy of etanercept from 62%, 38% and 16% to 49%, 26% and 7% for ACR20, ACR50 and ACR70 response rates respectively when used after one biological treatment. For tocilizumab when used after two biological treatments, degraded rates were based on the subgroup of people from the RADIATE trial whose rheumatoid arthritis had responded inadequately to more than one TNF‑alpha inhibitor. Based on these data, tocilizumab response rates changed from 62%, 31% and 12% to 50%, 31% and 15% for ACR20, ACR50 and ACR70 response rates respectively. For rituximab used after two biological treatments, the manufacturer provided downgraded response rates based on a subgroup of people whose rheumatoid arthritis had responded inadequately to more than one TNF‑alpha inhibitor from a trial comparing rituximab plus methotrexate with placebo plus methotrexate (REFLEX). Based on these data, the rituximab response rates were downgraded from 46%, 23% and 14% to 42%, 22% and 10% respectively.
3.29
The revised ICERs were based on the adjusted ACR rates from the mixed treatment comparison, and included a long-term HAQ improvement for tocilizumab and a stable HAQ score (that is, zero HAQ progression) for all other biological treatments. This was not the case for the ICER for tocilizumab given after rituximab, for which no HAQ improvement for treatment with any biological treatment, including tocilizumab, was assumed. All of the revised ICERs were calculated using the HAQ to EQ‑5D mapping and included negative utilities that represented states worse than death. The ICERs were subject to the assumption that a person would experience the same adverse events during treatment as during palliative care, and that the cost of administration of tocilizumab was £154.
3.30
The manufacturer's revised ICER for the DMARD‑IR population increased from £19,870 to £21,733 per QALY gained and increased from £22,003 to £23,285 per QALY gained for the TNF‑IR population. The ICER for tocilizumab used after rituximab was £23,735 per QALY gained. The ICER for tocilizumab for people who are intolerant to rituximab or for whom rituximab is contraindicated was £20,242 per QALY gained.
Decision Support Unit report 2010
3.31
In 2010, the DSU was asked to undertake additional cost-effectiveness analyses to validate the manufacturer's ICERs submitted following the third round of consultation, and to conduct sensitivity analyses to address the Appraisal Committee's concerns about key parameter assumptions. The 2010 report highlighted a key issue with the calculation of the ICERs presented by the manufacturer. This concerned the 'pair-wise' calculation of sequences containing tocilizumab plus methotrexate with the same sequence excluding tocilizumab rather than an 'incremental' comparison of all strategies containing tocilizumab plus methotrexate with each other and with a base-case strategy without tocilizumab. The DSU considered that the incremental approach was the most appropriate, not only to determine whether tocilizumab plus methotrexate was cost effective, but also in what circumstances, given the availability of a number of other treatments that are used sequentially. The DSU's 2010 report explained that an ICER calculated through a pair-wise comparison does not demonstrate that the sequence can be considered cost effective because there are a series of mutually exclusive sequences available and only one can be selected at any one time.
3.32
For etanercept, the mixed treatment comparison analysis combined all TNF‑alpha inhibitors (etanercept, infliximab and adalimumab) but excluded the Klareskog trial of etanercept that the Committee had requested to be removed because of its unusually high placebo response rate. The DSU noted in the 2010 report that the adjusted mixed treatment comparison rates were lower than the unadjusted trial ACR, or point estimate, rates for etanercept. The adjusted etanercept ACR20, ACR50 and ACR70 response rates were 62%, 38% and 16% respectively and the unadjusted ACR20, ACR50 and ACR70 response rates were 71%, 39% and 17% respectively. In 2010 the DSU reported that the unadjusted rates in the model were taken from a single etanercept trial, without justification for the sole use of this particular trial. The DSU provided an alternative set of unadjusted response rates for etanercept, which were based on the two etanercept trials from the mixed treatment comparison (rather than the single trial chosen by the manufacturer). The DSU stated in the 2010 report that this appeared to represent the most robust data. The resulting unadjusted ACR response rates were 73%, 47% and 22% for ACR20, ACR50 and ACR70 respectively. For rituximab, the adjusted mixed treatment comparison ACR response rates were also lower than the unadjusted ACR trial response rates. The percentage of people reaching an ACR20, ACR50 and ACR70 response rate was 51%, 27% and 12% respectively in the unadjusted analysis and 46%, 23% and 14% respectively in the adjusted analysis. The unadjusted data were taken from the REFLEX trial.
3.33
The DSU highlighted in the 2010 report that the opposite effect was observed with the adjusted and unadjusted ACR rates for tocilizumab, that is, the adjusted rates from the mixed treatment comparison were higher than the unadjusted rates. For tocilizumab given as the first biological treatment in the sequence, the adjusted rates were 63%, 41% and 26% for ACR20, ACR50 and ACR70 response rates respectively and the unadjusted rates for tocilizumab, which were based on a separate meta-analysis of OPTION, TOWARD and LITHE (submitted as part of the manufacturer's licence application), were 59%, 37% and 19% respectively. For tocilizumab used as the second biological treatment in a sequence (that is, after a TNF‑alpha inhibitor), the mixed treatment comparison had the same effect of increasing the tocilizumab ACR response rates. The adjusted rates were 62%, 31% and 12%, whereas the unadjusted rates were 50%, 29% and 12% for ACR20, ACR50 and ACR70 response rates respectively. The unadjusted rates for tocilizumab used as the second biological treatment in the sequence were taken from the RADIATE trial.
3.34
The DSU also commented on the degradation rates provided by the manufacturer. These rates were all from single data sources, without justification given for the selection of the sources. The DSU highlighted that the degraded response rates for etanercept were based on the reported ACR rates for the TNF‑alpha inhibitors as a group and may not have been generalisable to etanercept. The DSU also noted that the degraded ACR70 response rate for tocilizumab used after two biological treatments assumed by the manufacturer (15%) was marginally better than when used after a single biological treatment (12%). The DSU stated that this appeared to be counterintuitive and that it would be more appropriate to assume the same ACR70 response rate when tocilizumab is given after two biological treatments as for when it is given after one.
3.35
In the 2010 report the DSU considered four separate approaches that varied the ACR response rates and degradation rates used to calculate the incremental ICERs (approaches to evidence synthesis).
-
Approach 1 was the same as the manufacturer's revised base case and used the adjusted mixed treatment comparison results with the degradation rates supplied by the manufacturer.
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Approach 2 used the unadjusted single trial ACR response rates for etanercept when used first in the treatment sequence as supplied by the manufacturer. All other estimates remained the same as in approach 1.
-
Approach 3 used the unadjusted trial ACR response rates for all treatments in the sequence as supplied by the manufacturer. In addition, this approach replaced the degraded effect for tocilizumab when used after two biological treatments with the same effect assumed after one biological treatment to account for the counterintuitive change in response rate assumed by the manufacturer (see section 3.34).
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Approach 4 was the same as approach 3, except that the DSU used the alternative unadjusted ACR response rates for etanercept from the two trials (described in section 3.32).
3.36
For each of the four approaches to evidence synthesis, the DSU undertook four sets of sensitivity analyses to assess the robustness of the ICER results to other key parameter assumptions in the 2010 report. These were:
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employing the same set of parameter assumptions employed by the manufacturer in its base case
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assuming no long-term HAQ improvement with tocilizumab
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assuming no long-term HAQ improvement with tocilizumab and excluding negative utilities from the HAQ to EQ-5D mapping
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assuming no long-term HAQ improvement with tocilizumab and doubling the administration costs for tocilizumab to £308.60 per infusion.
3.37
The DSU in the 2010 report calculated the incremental ICERs for each approach using the four sensitivity analyses and presented the incremental results separately for each of the 16 possible analyses. In each incremental analysis, the treatment strategies compared with each other were:
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etanercept followed by rituximab (strategy 1)
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tocilizumab, followed by etanercept, followed by rituximab (strategy 2)
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etanercept, followed by tocilizumab, followed by rituximab (strategy 3)
-
etanercept, followed by rituximab, followed by tocilizumab (strategy 4).
3.38
For all treatment strategies, the calculation of the ICER included the costs and QALYs associated with treatment with conventional DMARDs and palliative care at the end of the sequence. All treatment strategies were in combination with methotrexate.
3.39
Using the threshold for cost effectiveness (£30,000 per QALY gained), the results of the fully incremental analysis undertaken by the DSU in the 2010 report indicated that using tocilizumab as a first-line treatment before etanercept would not be cost effective for any approach and with any set of parameter assumptions (including the manufacturer's base-case assumptions). Using tocilizumab as a second-line treatment before rituximab would only be cost effective if it is assumed that tocilizumab has long-term HAQ improvement and there is no HAQ improvement assumed with other biological treatments. However, if tocilizumab has zero HAQ improvement, then tocilizumab would only be cost effective when used as a third-line treatment after rituximab. If tocilizumab has zero HAQ improvement and the administration costs of tocilizumab are doubled, then tocilizumab is never cost effective (that is, standard care is the most cost-effective sequence). For people who have an intolerance to rituximab, or for whom rituximab is contraindicated, adding tocilizumab to the current standard care is cost effective. However, if tocilizumab does not have a different effect on long-term HAQ and the administration costs of tocilizumab are doubled, then the current standard care would be more cost effective for this population.
Rapid review of NICE technology appraisal guidance 198: patient access scheme
3.40
In the Appraisal Committee's original guidance on tocilizumab for rheumatoid arthritis (NICE technology appraisal guidance 198) tocilizumab plus methotrexate was recommended for the treatment of rheumatoid arthritis that has not responded adequately to one or more TNF‑alpha inhibitors or to rituximab, or in whom rituximab is contraindicated or is withdrawn because of an adverse effect. Following publication of this guidance, the manufacturer submitted a patient access scheme in which a discount was applied to all indications for tocilizumab (see section 2.4) to be considered as a rapid review of the original guidance.
3.41
As part of the rapid review, the manufacturer did not submit any additional clinical-effectiveness data. However, the manufacturer did clarify the ACR and non-response rates for each drug for each position in the treatment sequences. This highlighted that when tocilizumab is the first biological treatment in the sequence, the non-response rate is approximately 40% compared with 27% when etanercept is the first biological treatment in the sequence.
3.42
The manufacturer submitted revised ICERs using the assumptions that the Committee agreed at the final Committee meeting before issuing NICE technology appraisal guidance 198, which included:
3.43
The manufacturer presented the results of an incremental analysis for the DMARD‑IR population in which the following treatment sequences were included:
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etanercept then rituximab (baseline sequence)
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tocilizumab then etanercept then rituximab
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etanercept then tocilizumab then rituximab
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etanercept then rituximab then tocilizumab.
3.44
The manufacturer was requested to include an additional baseline treatment sequence of tocilizumab, followed by etanercept. In this analysis the ICER for tocilizumab as the first treatment in the sequence was £5716 per QALY gained. As the second treatment in the sequence it was £30,716 per QALY gained, and as the third treatment in the sequence the ICER was £8134 per QALY gained. All ICERs incorporated the discount for tocilizumab agreed as part of the patient access scheme.
3.45
The manufacturer also responded to a request from the DSU as part of this rapid review to provide ICERs for the TNF‑IR population in which the following treatment sequences were included:
3.46
In this analysis the costs and QALYs associated with prior treatment with a TNF‑alpha inhibitor were assumed to be the same for both treatment strategies and were therefore not modelled. The ICER for the tocilizumab sequence compared with the baseline sequence (incorporating the discount for tocilizumab agreed as part of the patient access scheme) was £22,690 per QALY gained.
Decision Support Unit report 2011
3.47
In 2011, the DSU was asked to undertake a review of whether the manufacturer had correctly implemented the Department of Health approved patient access scheme within their cost-effectiveness analysis. Additionally the DSU critiqued the changes to the costs of tocilizumab and ensured the Committee's agreed assumptions from the guidance on tocilizumab for rheumatoid arthritis (NICE technology appraisal guidance 198) had been used as the starting point within the economic analysis.
3.48
The DSU confirmed in the 2011 report that these conditions were met. However it raised the following issues with the manufacturer's analyses:
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No results had been presented for the subgroup of people intolerant to rituximab or who have had rituximab withdrawn because of a contraindication. The ICERs were incorrect because no account had been taken of sequences that were extendedly dominated (less effective than and at least as costly as a combination of other drug sequences).
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Within the TNF-IR analysis a sequence of rituximab followed by tocilizumab had not been included.
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The DSU also corrected for a minor inaccuracy in the unadjusted trial rates used in NICE technology appraisal guidance 198. This changed the ACR20, ACR50 and ACR70 response rates for tocilizumab following two biologicals from 0.50, 0.31 and 0.15 to 0.50, 0.29 and 0.12 respectively.
3.49
In 2011, the DSU reported the results of their exploratory analysis for the DMARD‑IR population, which included the same treatment sequences in an incremental analysis as those modelled by the manufacturer (see section 3.42). All ICERs incorporated the discount for tocilizumab agreed as part of the patient access scheme. In this analysis, three sequences were extendedly dominated (first: etanercept followed by rituximab; second: tocilizumab as the first treatment; third: tocilizumab as the second treatment). The ICER for tocilizumab as the third treatment in the sequence was £28,380 per QALY gained compared with £8134 per QALY gained from the manufacturer's analysis.
3.50
The DSU provided an additional exploratory analysis in the 2011 report. This was an exploratory analysis for the rituximab-intolerant DMARD-IR population. All ICERs incorporated the discount for tocilizumab agreed as part of the patient access scheme. In this analysis etanercept alone was extendedly dominated. The ICER for tocilizumab followed by etanercept compared with tocilizumab alone was £10,698 per QALY gained, and the ICER for etanercept followed by tocilizumab compared with tocilizumab followed by etanercept was £30,121 per QALY gained.
3.51
The DSU reported the results of their exploratory analysis for the TNF-IR population, which included the same treatment sequences in an incremental analysis as those modelled by the manufacturer (see section 3.43). All ICERs incorporated the discount for tocilizumab agreed as part of the patient access scheme. In this analysis, tocilizumab followed by rituximab was dominated (was less effective than and at least as costly) by rituximab followed by tocilizumab. The ICER for rituximab followed by tocilizumab was £18,527 per QALY gained compared with the manufacturer's estimate of £22,690 per QALY gained.
3.52
Full details of all the evidence are in the manufacturer's submissions, the ERG report, and the reports from the DSU, which are available from the NICE website.