DOI: 10.12809/hkmj144336
© Hong Kong Academy of Medicine. CC BY-NC-ND 4.0
LETTER TO THE EDITOR
Cost-effectiveness of epidermal growth factor receptor–targeting tyrosine kinase inhibitors
John SM Leung, FCSHK, FHKAM (Surgery)
St Paul’s Hospital, Hong Kong
Corresponding author: Dr John SM Wong (leungsiumanjohn@yahoo.com.hk)
To the Editor—I read with great interest, in the recent
issue of the Hong Kong Medical Journal, the article
“Effectiveness and cost-effectiveness of erlotinib
versus gefitinib in first-line treatment of epidermal
growth factor receptor-activating mutation-positive
non–small-cell lung cancer patients in Hong Kong”
by Lee et al.1 The authors, by indirect treatment
comparison, demonstrated the cost-effectiveness of
erlotinib over gefitinib. However, I find it difficult
to understand the rationale behind the basis of this
comparison. The approach compares trial [A vs C]
with trial [B vs C], using C as the bridge comparator.
By substitution, the authors cited IPASS2 with
gefitinib-treated patients (A) versus carboplatin-paclitaxel–treated patients (C) for comparison with OPTIMAL3 with erlotinib-treated patients (B) versus carboplatin-gemcitabine–treated patients (C). Obviously the
C’s in the two trials are not identical unless it can be
proven that carboplatin-paclitaxel and carboplatin-gemcitabine
have exactly the same efficacy. Furthermore the patient characteristics in the two
trials are also not identical. In IPASS only some
patients were shown to have epidermal growth factor
receptor (EGFR) mutations, while in OPTIMAL all
patients had EGFR-activating mutations in exons 19
and 21. Since such mutations determine the response
to treatment targeting tyrosine kinase inhibitors,
patients receiving erlotinib (in OPTIMAL) had a
clear advantage.
As Lam and Mok4 pointed out in their
editorial commentary, head-to-head comparison
is the preferred method of assessment and such
studies have been done in Korea, Taiwan and China,
showing no significant difference in efficacy between
gefitinib and erlotinib except a better toxicity profile
for the former. I fully agree with the editors that we
should move on beyond these two drugs.
As to cost-effectiveness, it might be worthwhile
to take note of a third EGFR inhibitor, icotinib. In a
head-to-head comparison trial,5 it has been shown
to be non-inferior to gefitinib but with an even better
toxicity profile. Developed in China, it is said to cost
considerably less than either erlotinib or gefitinib.
Hope it becomes available in Hong Kong soon.
Declaration
No conflicts of interests were declared by author.
References
1. Lee VW, Schwander B, Lee VH. Effectiveness and cost-effectiveness
of erlotinib versus gefitinib in first-line
treatment of epidermal growth factor receptor-activating
mutation-positive non-small-cell lung cancer patients in
Hong Kong. Hong Kong Med J 2014;20:178-86.
2. Fukuoka M, Wu YL, Thongprasert S, et al. Biomarker
analyses and final overall survival results from a phase III
randomized, open-label, first-line study of gefitinib versus
carboplatin/paclitaxel in clinically selected patients with
advanced non-small-cell lung cancer in Asia (IPASS). J Clin
Oncol 2011;29:2866-74. CrossRef
3. Zhou C, Wu YL, Liu X, et al. Overall survival (OS) results
from OPTIMAL (CTONG0802), a phase III trial of erlotinib
(E) versus carboplatin plus gemcitabine (GC) as first-line
treatment for Chinese patients with EGFR mutation-positive
advanced non-small cell lung cancer (NSCLC)
[abstract]. J Clin Oncol 2012;30(Suppl);abstract 7520.
4. Lam KC, Mok TS. Comparison is beyond IPASS and
OPTIMAL. Hong Kong Med J 2014;20:176-7. CrossRef
5. Shi Y, Zhang L, Liu X, et al. Icotinib versus gefitinib in
previously treated advanced non-small-cell lung cancer
(ICOGEN): a randomised, double-blind phase 3 non-inferiority
trial. Lancet Oncol 2013;14:953-61. CrossRef