Autologous cell therapy continues to show benefit in patients with LV dysfunction after STEMI

SAN DIEGO — At 12-month follow-up, autologous CD34+ cell therapy for patients with left ventricular dysfunction after STEMI was safe and well tolerated, and showed a signal of mortality benefit and reduced serious adverse events in higher-dose groups, according to new data from the PreSERVE-AMI study.

Arshed A. Quyyumi, MD, FCRP, from Emory University School of Medicine, presented updated results from the phase 2 PreSERVE-AMI study at the American College of Cardiology Scientific Sessions. All patients completed 12-month follow-up, and the data reflected a median of 18 months follow-up.

Arshed A. Quyyumi*

The researchers randomly assigned patients with STEMI, successful stent placement and LV ejection fraction ≤ 45% on cardiac MRI or ≤ 48% on single-photon emission CT to receive NBS10 (NeoStem Inc.), a formulation of autologous CD34+ cells known to enhance and preserve functional CXCR4 expression, or matching cell-diluent placebo, administered 6 to 11 days after stent placement. Of those randomized, 78 (mean age, 57.1 years; 15% women) were able to receive infusion of NBS10 and 83 (mean age, 56.4 years; 20% women) were able to receive infusion of placebo.

During the median 18-month follow-up period, there were no cardiac deaths in the cell therapy group and three in the placebo group (P = .04; log-rank P = .055), Quyyumi said.

Major adverse cardiac event rates were 14% in both groups; however, patients who received a dose of more than 14 million cells had an event rate of 10%, and those who received a dose of more than 20 million cells had an event rate of 7% (P = .055), according to the researchers.

The proportion of serious adverse events normalized by total participants was 1.2 in the placebo group and 0.9 in the cell-therapy group, but was 0.6 in those receiving a dose of more than 14 million cells (P = .059) and 0.7 in those receiving a dose of more than 20 million cells, according to the findings.

Improvement in clinically relevant endpoints was not mirrored by a change in SPECT perfusion, which indicates that SPECT myocardial perfusion is not a suitable surrogate, Quyyumi said.

From baseline to 6 months, patients who received a dose of more than 20 million cells had a 10.2% improvement in LVEF compared with 4.9% for controls (P < .05), he said.

Infarct size reduction from baseline to 6 months was –24% for controls and –23% for the cell-therapy group, but was –35% for those receiving a dose of more than 14 million cells and –41% for those receiving a dose of more than 20 million cells, according to the findings.

“While small in number, we are encouraged by the fewer mortality events observed for treated patients vs. control patients as of the date of this 12-month follow-up,” Quyyumi said in a press release. “In addition, we are very encouraged by the persistence of reduced serious adverse event rates and evidence for improved infarct healing and [LV] function. In addition, the failure of SPECT imaging to document changes at the 6 month interim analysis, despite signs of clinical benefit in multiple parameters, suggests this technique is not applicable in this setting.” – by Erik Swain

Reference:

Quyyumi AA, et al. Highlighted Original Research: Stable Ischemic Heart Disease and the Year in Review. Presented at: American College of Cardiology Scientific Sessions; March 14-16, 2015; San Diego.

Disclosure: The study was funded by NeoStem Inc. Quyyumi reports serving on an advisory board for NeoStem.

*Photo courtesy Jack Kearse, Emory University