Treatment of glioblastoma multiforme with "classic" 4:1 ketogenic diet total meal replacement.
Level 4 - case-series / case-control
Uncontrolled prospective pilot trial / case series
PubMed 33292598 · doi:10.1186/s40170-020-00230-9
What was done
This open-label pilot study evaluated the feasibility, safety, tolerability, and preliminary efficacy of a "classic" 4:1 (fat to protein plus carbohydrate by weight, 10 g carbohydrate/day, 1600 kcal/day) ketogenic diet delivered via a total meal replacement program with standardized ready-made meals for 6 months in glioblastoma (GBM) patients. Eight patients participated across two cohorts: newly diagnosed GBM receiving diet adjunctively to radiation and temozolomide (group 1, n = 4) and recurrent GBM (group 2, n = 4). Patients monitored twice-daily blood glucose and blood/urine ketones and underwent regular MRIs. Primary outcomes were retention, treatment-emergent adverse events (TEAEs), and TEAE-related discontinuation; secondary outcomes were survival time from diet initiation and time to MRI progression.
What was found
The study was terminated early due to slow recruitment after enrolling 8 patients. Five patients (62.5%) completed the 6-month treatment (4/4 in group 1, 1/4 in group 2). Three patients stopped early: 2 (25%) from GBM progression and 1 (12.5%) due to diet restrictiveness; no patients discontinued due to TEAEs. Reported TEAEs were mild and transient, including weight loss and hunger (n = 6), nausea (n = 2), dizziness (n = 2), fatigue (n = 1), and constipation (n = 1). Seven patients died. Mean survival from diet initiation was 20 months (range 9.5–27) for group 1 and 12.8 months (range 6.3–19.9) for group 2. Mean survival from diagnosis was 21.8 months (range 11–29.2) for group 1 and 25.4 months (range 13.9–38.7) for group 2. One patient with recurrent GBM experienced tumor shrinkage, edema resolution, and symptom reversal at 6–8 weeks, surviving 20 months post-diet initiation.
Why it matters
The study shows that a standardized 4:1 ketogenic total meal replacement regimen is feasible and well-tolerated in glioblastoma patients without severe adverse effects.
Limits
The study is severely limited by its very small sample size (n = 8), early trial termination, open-label design, and lack of a control comparator, preventing reliable conclusions about therapeutic efficacy.
Cited by
- supports A classical 4:1 ketogenic diet consists of 90% fat and one part protein and carbohydrates combined.