Abstract 231P
Background
In the randomized, double-blind, phase 3 trial SOLO1, olaparib (OLA) in the maintenance setting demonstrated a 70% lower risk of disease progression or death than placebo in women with newly diagnosed advanced ovarian cancer and a BRCA1/2 mutation. This study aimed to evaluate the cost-effectiveness of OLA maintenance therapy versus routine surveillance (RS) after response to first-line platinum-based chemotherapy in this population in Singapore.
Methods
A three-state partitioned survival model was developed to simulate the lifetime (50 years) incremental cost-effectiveness ratio (ICER) of OLA versus RS from a healthcare payer perspective. Progression-free and overall survival curves were estimated using data from SOLO1 and extrapolated beyond the trial period using parametric survival models. Any patient who remained progression-free at year 7 was assumed to be a long-term survivor and no longer at risk of progression. Mortality rates for this group were modelled on all-cause mortality from the general population adjusted for BRCA1/2 mutation status. These assumptions were validated with local clinicians. Health state utilities and adverse event frequencies were obtained from SOLO1. Drug costs were sourced from local public healthcare institutions. Healthcare resource usage and costs were based on local clinician input and publications. A 3% discount rate was applied to costs and outcomes. Deterministic and probabilistic sensitivity analyses (PSA) were performed to assess the robustness of results.
Results
The base-case analysis of OLA maintenance therapy versus RS resulted in an ICER of SGD17,326 per quality-adjusted life year (QALY) gained. The ICER was most sensitive to variations in the discount rate and mortality risk in long-term survivors. PSA demonstrated that OLA was associated with an 81% probability of being cost-effective at a willingness-to-pay threshold of SGD50,000 per QALY gained.
Conclusions
OLA has a high potential of being a cost-effective maintenance therapy versus RS for patients with BRCA1/2 mutated advanced ovarian cancer after response to first-line chemotherapy in Singapore.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
AstraZeneca Singapore Pte Ltd.
Funding
AstraZeneca Singapore Pte Ltd.
Disclosure
D.S. Tan: Honoraria (self): AstraZeneca; Honoraria (self): Novartis; Honoraria (self): Roche; Honoraria (self): MSD; Honoraria (self): Bayer; Honoraria (self): Genmab; Honoraria (self): Tessa Therapeutics; Honoraria (self): Merck Serono ; Research grant / Funding (institution): AstraZeneca; Research grant / Funding (institution): Karyopharm Therapeutics; Research grant / Funding (institution): Bayer; Research grant / Funding (institution): Roche (Foundation Medicine); Research grant / Funding (self): National Medical Research Council Singapore Clinician Scientist Award; Advisory / Consultancy: AstraZeneca; Advisory / Consultancy: Roche; Advisory / Consultancy: Bayer; Advisory / Consultancy: ETC/D3 Singapore; Advisory / Consultancy: Tessa Therapeutics; Advisory / Consultancy: Genmab. J.J. Chan: Honoraria (self): Novartis; Honoraria (self): AstraZeneca; Honoraria (self): Merck Sharp & Dohme; Advisory / Consultancy: Eisai; Advisory / Consultancy: Pfizer; Research grant / Funding (institution): OncoQuest Inc; Research grant / Funding (institution): Pfizer; Travel / Accommodation / Expenses: Synthon; Travel / Accommodation / Expenses: Novartis; Travel / Accommodation / Expenses: AstraZeneca; Travel / Accommodation / Expenses: Celgene. J.K. Loke: Full / Part-time employment: AstraZeneca. R. Hettle: Full / Part-time employment: AstraZeneca. C.C. Yu: Full / Part-time employment: AstraZeneca. All other authors have declared no conflicts of interest.
Resources from the same session
107P - The efficacy of adjuvant chemotherapy according to the risk classification of recurrence based on the systemic inflammatory markers in patients with colorectal cancer liver metastases
Presenter: Masatsune Shibutani
Session: Poster display session
Resources:
Abstract
108P - Influence of liver metastasis locations on overall survival in patients with colorectal cancer
Presenter: Takayuki Sone
Session: Poster display session
Resources:
Abstract
109P - 18F-FDG PET/CT textural features as predictors of outcomes in patients with primary advanced colorectal cancer
Presenter: Jing Yang
Session: Poster display session
Resources:
Abstract
110P - D3 lymph node dissection may be necessary in clinical stage I right colon cancer
Presenter: Woong Bae Ji
Session: Poster display session
Resources:
Abstract
111P - Is preoperative chemoradiotherapy necessary for all patients with upper rectal cancer: One center retrospective study
Presenter: Jasur Madyarov
Session: Poster display session
Resources:
Abstract
112P - A retrospective analysis of the association between perioperative, post adjuvant carcinoembryonic antigen level and prognosis in stage III colorectal cancer
Presenter: Ryotaro Kozuki
Session: Poster display session
Resources:
Abstract
113P - Dicer contributes to chemoresistance in colorectal cancer via regulating a set of miRNAs and their downstream mRNAs
Presenter: Liang-Yi Hung
Session: Poster display session
Resources:
Abstract
114P - Efficacy and safety of the combination of bevacizumab with raltitrexed-based chemotherapy as second-line therapy in patients with metastatic colorectal cancer (mCRC): An interim analysis of a multicenter phase II trial
Presenter: Jun Zhu
Session: Poster display session
Resources:
Abstract
115P - Expression of Ki-67 as a prognostic factor in patients with colorectal cancer
Presenter: Kuantkan Zhabagin
Session: Poster display session
Resources:
Abstract
116P - Clinical significance and converionrate relevance of RAS genetic mutation analysis for unresectable colorectal liver metastases: A single-center retrospective study
Presenter: Meiling Ji
Session: Poster display session
Resources:
Abstract