REAL-WORLD TREATMENT ADHERENCE AND OVERALL SURVIVAL IN CANCER PATIENTS RECEIVING PEMBROLIZUMAB THROUGH A PATIENT ASSISTANCE PROGRAM AT MILITARY HOSPITAL 175

Nguyen Tien Dung1, Ha Manh Duc1, Tran Duc Linh1, Nguyen Thi Lan1, Tran Viet Hieu1, Tran Viet Hieu1, Bui Thi Hang1, Hoang Thi Lam1, Thai Huu Tinh1, Bui Hoang Hai1, Le Thi Linh2, Nguyen Khac Tuyen3
1 Military Hospital 175
2 Bồi Sơn Health Station
3 Tam Anh General Hospital, Ho Chi Minh City

Main Article Content

Abstract

Objectives: To describe study-defined treatment continuation, overall survival (OS), and factors associated with mortality among cancer patients participating in the Vietnam Patient Assistance Program (VPAP) at Military Hospital 175.


Subjects and methods: This single-center retrospective cohort study included 191 adults receiving Pembrolizumab through VPAP. Treatment continuation was operationally defined as receipt of ≥ 80% of the planned Pembrolizumab cycles. OS was measured from treatment initiation within VPAP to death from any cause; patients alive were censored at their last follow-up. Survival was estimated using Kaplan-Meier methods, and mortality-associated factors were analyzed using Cox regression.


Results: The median age was 62 years, and 71.7% were male. Overall, 79.6% met the study-defined treatment-continuation criterion, and median OS was 8 months. In the multivariable Cox model, ECOG performance status ≥ 2 (adjusted HR 11.82, 95% CI: 5.84-23.90; p < 0.001) and age ≥ 65 years (adjusted HR 1.71, 95% CI: 1.10-2.67; p = 0.018) were associated with higher mortality. The combination-chemotherapy group had a lower adjusted hazard of death; this observational association may remain affected by confounding by indication.


Conclusions: In this cohort, 79.6% met the operational treatment-continuation criterion. Poor ECOG performance status and older age were independently associated with shorter survival. Regimen-group findings should not be interpreted as causal treatment-effect estimates.

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References

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