SiltuximabSYLVANT
Treatment of idiopathic multicentric Castleman disease (iMCD) in patients who are HIV-negative and HHV-8 negative.
Decisions on record
- Meeting Nov 2021 Recommended Idiopathic multicentric Castleman's disease (iMCD)
- Meeting Jul 2021 Not recommended Idiopathic multicentric Castleman disease
Access path
- TGA registered · SYLVANT
TGA label narrower than the PBS population
- Jul 2021Not recommended
vs placebo
- ↻ resubmittedNov 2021Recommended · restricted
- PBS listing · Authority Required
From the public summary
5.1 The PBAC recommended the Authority Required (immediate assessment) listing of siltuximab for the treatment of idiopathic Multicentric Castleman disease (iMCD). The resubmission provided a revised economic model and financial estimates in response to previous concerns raised by the PBAC.PSD · Nov 2021
5.2 The PBAC is satisfied that siltuximab provides, for some patients, a significant improvement in efficacy over placebo. The PBAC’s recommendation for listing was based on, among other matters, its assessment, as described above, that the cost- effectiveness of siltuximab would be acceptable at the price proposed in the pre-PBAC response.PSD · Nov 2021
4.5 A summary of the key matters to be addressed is presented in Table 2.PSD · Nov 2021
Table 2: Summary of key matters to be addressed – economic model Resubmission Matter of concern Utility values The PBAC considered that the reliability of the model was improved by using more conservative assumptions in the respecified model provided with the pre-PBAC response. The resubmission provided additional justification for the However, the PBAC noted that the respecified model had proposed utility values.PSD · Nov 2021
The submission described siltuximab as superior in terms of efficacy and similar in terms of safety compared to placebo. The evaluation considered this claim was reasonable in terms of efficacy but not in terms of safety.PSD · Jul 2021
The PBAC agreed with the ESC that the claim of superior efficacy compared to placebo was reasonable for the primary outcome of durable tumour and symptomatic response.PSD · Jul 2021
4.2 The PBAC noted and welcomed the input from two individuals via the Consumer Comments facility on the PBS website. The comments from individuals described improved health and wellbeing while on treatment with siltuximab, and expressed concern about affordability if the drug is not PBS listed.PSD · Nov 2021
4.3 The PBAC also noted that in July 2021 input was received from 11 individuals, 6 health care professionals and 1 organisation (paragraph 6.2, siltuximab PSD, July 2021 PBAC Meeting).PSD · Nov 2021
Cost-effectiveness
ICER range redacted; stated as '$75,000 to < $95,000/QALY' in the resubmission base case at 20-year time horizon. At 15-year horizon (not requested by PBAC), ICER would also be in the same redacted range.
Decision context
PopulationPatients with idiopathic multicentric Castleman disease (iMCD) who are HIV-negative and HHV-8 negative, meeting international consensus diagnostic criteria for histopathologic and clinical/laboratory features.
Submission history
| Decided | Outcome | Comparator | ICER | Evidence |
|---|---|---|---|---|
| Nov 2021 | Recommended · restricted | placebo | $75k–95k | RCT · QoL |
| Jul 2021 | Not recommended | placebo | — | RCT · Tumour response |
Consumer voice
Two individuals provided comments describing improved health and wellbeing while on siltuximab treatment and expressed concern about affordability if the drug is not PBS listed. Previous input from 11 individuals, 6 healthcare professionals, and 1 organisation was also noted.
The comments from individuals described improved health and wellbeing while on treatment with siltuximab, and expressed concern about affordability if the drug is not PBS listed. Consumer comments · PSD
Similar precedents
Regulatory · TGA
Label narrower than PBS population — PBAC restricts to idiopathic MCD (iMCD) with international consensus diagnostic criteria; TGA label includes all MCD regardless of etiology.