Abstract 1578P
Background
Although correlation studies of surrogate endpoints in oncology and value-frameworks to assess magnitude of clinical benefit of cancer drugs are available, studies assessing the perception of oncologists, specially those working in low-and-middle-income countries (LMICs), regarding endpoints and value of drugs are lacking.
Methods
We conducted a mixed-methods study including in-depth qualitative interviews of medical oncologists prescribing cancer drug therapy in India. Quantitative data was collected using a predetermined proforma. Qualitative in-depth interviews were audio-recorded, transcribed verbatim, anonymized, subsequently coded, and analyzed by generating basic and global themes.
Results
We interviewed 25 medical oncologists (median age 40, number of years in oncology practice 10, males 76%). 28% of oncologists rarely used cancer drugs that improved response rate (RR) but not overall survival (OS), and an equal percentage mostly/often used such drugs. For cancer drugs that improved PFS but not OS, 20% never/rarely used them while 48% mostly/often used them. Oncologists in India considered a 4.5-month (range, 1.5-12) advantage in median PFS as meaningful, and considered price of up to 10,000 INR (∼120 USD) per month (range, 4000-60,000 INR) for those PFS gains as justified. For OS, median gains of 4.5 months (range, 2-24) and at a monthly price of 30,000 INR (∼360 USD) (range, 15000-50,000 INR) was considered justified. Oncologists in India were aware and concerned that RR only showed tumor shrinkage not survival benefit, but many also assumed that tumor shrinkage would lead to symptom relief and better quality of life. Many oncologists acknowledged the limitations of PFS but would use a drug with PFS benefit if it was cheaper than the drug with OS benefit.
Conclusions
Oncologists in India showed awareness of the limited surrogacy between RR/PFS and OS but assumed that RR/PFS correlated with improved QOL and acknowledged that price would be a factor in deciding treatment choices. This is the first study providing benchmark for minimum clinical benefit (4.5 months in PFS or OS) and maximum monthly price (120 USD for PFS, 360 USD for OS) deemed justifiable by oncologists practicing in LMIC settings.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
S.S. Datta.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
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