# Phase 2 trial of 1000 mg daily vitamin C in 109 patients: exploratory analysis shows lower mortality

- Published: 2026-11-12 03:39 UTC
- Section: Life & Health › Medicine
- Tags: vitamin C trial, EVITA trial, lower risk myeloid malignancies, TET2 mutations, overall survival hazard ratio, phase 2 randomized trial, placebo-controlled trial, leukemia precursor conditions
- URL: https://realtech.media/news/rt-94269948006729c62088f391_phase_2_trial/

**In the randomized EVITA trial the primary endpoint, clonal growth rate, did not differ between groups, but overall survival was longer with vitamin C in an exploratory analysis.**

![Phase 2 trial of 1000 mg daily vitamin C in 109 patients: exploratory analysis shows lower mortality](https://realtech.media/media/2026/11/bd58f522b0763f10.jpg)
*science-et-vie.com*

The University of Copenhagen and the Van Andel Institute reported results of EVITA, a double-blind, randomized, placebo-controlled phase 2 trial of oral vitamin C, in the journal Cancer [1]. The trial ran in Denmark and the United States and enrolled 109 adults between November 1, 2017, and September 28, 2022: 55 received vitamin C and 54 received placebo [1]. The paper was published on 21 September 2026.

Participants had clonal cytopenia of undetermined significance (CCUS) or lower risk myeloid malignancies and were not receiving anticancer therapy. They were assigned 1:1 to 1000 mg of oral vitamin C per day or placebo for 12 months, followed by long-term follow-up [1]. The rationale is that vitamin C is a cofactor for TET enzymes involved in DNA demethylation. Mutations in TET2 are common drivers of leukemia, and preclinical studies suggest that vitamin C may delay progression [1].

## Primary endpoint and safety

The primary endpoint was the median clonal growth rate from baseline to the end of treatment. It did not differ between the vitamin C and placebo groups [1]. Secondary outcomes included differences in inflammatory cytokine trajectories and fewer serious adverse events in the vitamin C group: 18 of 55 (33%) versus 30 of 53 (57%) with placebo [1].

According to the Science et Vie account of the study, more than half of the participants were vitamin C deficient at the start, and those who received the tablets reached normal levels within weeks. The same account says inflammatory markers rose more slowly in the treated group.

## Survival in an exploratory analysis

In exploratory analyses, overall survival was significantly longer with vitamin C: the hazard ratio was 0.35 (95% CI, 0.17 to 0.71) [1]. Science et Vie describes this as a 65% lower probability of death. It also reports a median follow-up of 33.6 months, with 11 deaths in the vitamin C group and 24 in the placebo group.

The same account says five treated patients and nine placebo patients progressed to an aggressive blood cancer. It states that this difference does not reach statistical significance in a sample of this size.

The authors conclude that oral vitamin C is a safe, biologically active intervention in patients with early-stage myeloid malignancies and precursor conditions, and that a phase 3 trial is warranted [1]. First author Stine Ulrik Mikkelsen noted that a phase 3 trial will have to confirm the data. Her team plans to study how vitamin C interacts with precancerous cells and whether it restores TET2 function when the enzyme is altered.

## Sources

1. [Cancer](https://doi.org/10.1002/cncr.70549)
2. [science-et-vie.com](https://www.science-et-vie.com/corps-et-sante/un-essai-sur-109-personnes-presentant-un-risque-de-leucemie-associe-1-000-mg-de-vitamine-c-par-jour-a-un-risque-de-deces-inferieur-de-65-265953.html)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-94269948006729c62088f391_phase_2_trial/