Compound reference
Cerebrolysin
Cerebrolysin is a porcine brain-derived peptide mixture used in many countries for stroke, dementia, and brain injury. Unlike most research peptides it has real randomized trials — but the pooled evidence is mixed and often low-quality, it is not a single defined molecule, and it is not FDA-approved.
Regional peptide mixture; not FDA-approved as a drug in the United States.
Mode of action
Cerebrolysin is unusual among the compounds in this library because it is not a single molecule. It is a standardized mixture produced by the enzymatic breakdown of purified porcine brain proteins, yielding a blend of low-molecular-weight neuropeptides and free amino acids. The proposed mechanism is neurotrophic and neuroprotective — the peptide fraction is thought to mimic the actions of endogenous neurotrophic factors, supporting neuronal survival, neuroplasticity, and repair after injury. Because it is a complex biological mixture rather than a defined compound, it has no single chemical formula, sequence, or CAS number, and its "active ingredients" are not fully resolved.
Main intended effect
Neuroprotection and neurorecovery — supporting functional recovery after acute brain injury (stroke, traumatic brain injury) and slowing cognitive decline in dementia.
Areas of interest
Cerebrolysin is used clinically — in many countries across Europe and Asia, though not in the United States — for acute ischemic stroke, vascular dementia, Alzheimer's disease, traumatic brain injury, and neurorehabilitation. It is administered by intravenous infusion in courses rather than sold primarily as a self-administered "research peptide."
Evidence for intended effects
Cerebrolysin's evidence base is, unusually, built on actual randomized controlled trials — which makes the honest reading a question of quality and consistency rather than presence. On the positive side, the CARS trial reported improved motor recovery after stroke, a dedicated Alzheimer's dose-finding trial explored cognitive endpoints, and a TBI trial (CAPTAIN I) suggested benefit on neurorecovery outcomes.
On the cautionary side, the pooled and independent analyses are far more tempered. A Cochrane review of Cerebrolysin in acute ischemic stroke (seven trials, ~1,773 participants) found no convincing evidence of benefit on death or dependency, and a Cochrane review in vascular dementia found only low-quality evidence of a possible cognitive effect. So the picture is of a long-used preparation with real but inconsistent and often low-certainty evidence — some individual positive trials, but meta-analyses that do not establish a clear benefit.
| Strand | What exists | Tier |
|---|---|---|
| Stroke recovery | CARS RCT positive; Cochrane (acute stroke) no clear benefit | Mixed |
| Vascular dementia | Cochrane review — low-quality evidence of effect | Low-quality |
| Alzheimer's / TBI | Dose-finding and CAPTAIN I trials | Limited |
| Defined active component | Complex mixture; not resolved | N/A |
Studied amounts (literature dosing context)
Trials administered Cerebrolysin by intravenous infusion in defined courses — for example daily doses in the range of roughly 10–60 mL given over several weeks (often 5 days/week), with dose varying by indication. These are clinical-trial regimens from the regions where it is marketed; this page does not provide dosing guidance.
Safety and regulatory status
In its trials Cerebrolysin has generally been reported as well tolerated. It is an approved and marketed medicine in a number of countries, but it is not FDA-approved in the United States, where it is neither a recognized drug nor a defined research peptide. Because it is a biologically derived mixture, batch standardization and the porcine source are themselves considerations. Anyone encountering "Cerebrolysin" outside its regional medical use should treat it as an unapproved product of variable, mixture-based composition.
Sources
Cerebrolysin and Recovery After Stroke (CARS): A Randomized, Placebo-Controlled, Double-Blind, Multicenter Trial
The CARS trial (Muresanu and colleagues) was a prospective, randomized, double-blind, placebo-controlled, multicenter study of 208 patients (104 Cerebrolysin, 104 placebo) with acute ischaemic stroke. Patients received 30 mL/day of intravenous Cerebrolysin or saline once daily for 21 days, beginning 24-72 hours after stroke onset, alongside standardized rehabilitation. The primary endpoint was upper-extremity motor function on the Action Research Arm Test (ARAT) at day 90, where the analysis reported a large superiority of Cerebrolysin (Mann-Whitney estimator 0.71, 95% CI 0.63-0.79; P<0.0001). The authors described the study as exploratory with a relatively small sample size, requiring confirmation in a large-scale phase III trial. Cerebrolysin is not FDA-approved and its approval status varies by country.
Cerebrolysin for acute ischaemic stroke
This Cochrane systematic review and meta-analysis (Ziganshina and colleagues) pooled seven randomized controlled trials with 1,773 participants comparing Cerebrolysin (and one Cortexin trial, 272 participants) against placebo as add-on therapy for acute ischaemic stroke. Moderate-certainty evidence indicated the peptide mixtures probably result in little to no difference in all-cause death (RR 0.96, 95% CI 0.65-1.41) and little to no difference in the total number of people with serious adverse events (RR 1.16, 95% CI 0.81-1.66), but a signal of increased non-fatal serious adverse events was seen (RR 2.39, 95% CI 1.10-5.23). The authors flagged substantial risk of bias, including pervasive manufacturer involvement in the included trials and high attrition. They concluded the available evidence does not establish a clinical benefit of Cerebrolysin for acute ischaemic stroke. Cerebrolysin is approved and used in several countries but is not FDA-approved, and its regulatory status varies by country.
Cerebrolysin for vascular dementia
This Cochrane systematic review (Cui and colleagues) examined six randomized controlled trials enrolling 597 participants with mild-to-moderate vascular dementia treated with intravenous Cerebrolysin versus placebo or control. Cognition and global function were assessed with instruments including the MMSE, ADAS-cog+, and the Hasegawa Dementia Scale. Pooled analysis suggested courses of intravenous Cerebrolysin improved cognition and general function with no signal of adverse effects, but the authors rated the certainty of evidence as very low and cautioned that effects may be too small to be clinically meaningful. Most included trials were small, conducted largely in China, and several were pharmaceutical-industry supported. The review called for adequately powered, methodologically rigorous trials before routine use. Cerebrolysin is not FDA-approved and its regulatory and approval status varies by country.
A 24-week, double-blind, placebo-controlled study of three dosages of Cerebrolysin in patients with mild to moderate Alzheimer's disease
Alvarez and colleagues randomized 279 patients with mild-to-moderate Alzheimer's disease to intravenous Cerebrolysin at 10, 30, or 60 mL or to placebo, infused 5 days/week for 4 weeks and then twice weekly for 8 weeks across a 24-week study. Cognition was assessed with the modified ADAS-cog and global change with the CIBIC+. At week 24 the 10 mL dose showed significant improvement in cognition (ADAS-cog, P=0.038) and global function, while the 30 mL and 60 mL doses improved global outcome but not cognition, suggesting a reversed U-shaped dose-response. The single-trial design and dose-dependent inconsistency limit interpretation. Cerebrolysin is not FDA-approved and its approval status varies by country; efficacy for Alzheimer's disease is not established.
Safety and efficacy of Cerebrolysin in acute brain injury and neurorecovery: CAPTAIN I—a randomized, placebo-controlled, double-blind, Asian-Pacific trial
CAPTAIN I (Poon and colleagues) was a randomized, double-blind, placebo-controlled trial of 46 traumatic brain injury patients (22 Cerebrolysin, 24 placebo) treated on top of standard care with intravenous Cerebrolysin 50 mL/day for 10 days followed by two cycles of 10 mL/day for 10 days. The primary endpoint was a multidimensional ensemble of 14 functional and neuropsychological outcome scales analyzed by the multivariate Wei-Lachin procedure. Per-protocol analysis showed statistically significant superiority favoring Cerebrolysin, with three individual measures showing significant gains in cognitive processing speed. The investigators noted the small sample and called for confirmation in larger randomized controlled trials. Cerebrolysin is not FDA-approved and its approval status varies by country; human efficacy in TBI is not established.