Welcome to The Nonlinear Library, where we use Text-to-Speech software to convert the best writing from the Rationalist and EA communities into audio. This is: WTH is Cerebrolysin, actually?, published by gsfitzgerald on August 6, 2024 on LessWrong.

[This article was originally published on Dan Elton's blog, More is Different.]

Cerebrolysin is an unregulated medical product made from enzymatically digested pig brain tissue. Hundreds of scientific papers claim that it boosts BDNF, stimulates neurogenesis, and can help treat numerous neural diseases. It is widely used by doctors around the world, especially in Russia and China.

A recent video of Bryan Johnson injecting Cerebrolysin has over a million views on X and 570,000 views on YouTube. The drug, which is advertised as a "peptide combination", can be purchased easily online and appears to be growing in popularity among biohackers, rationalists, and transhumanists. The subreddit r/Cerebrolysin has 3,100 members.

TL;DR

Unfortunately, our investigation indicates that the benefits attributed to Cerebrolysin are biologically implausible and unlikely to be real. Here's what we found:

Cerebrolysin has been used clinically since the 1950s, and has escaped regulatory oversight due to some combination of being a "natural product" and being grandfathered in.

Basic information that would be required for any FDA approved drug is missing, including information on the drug's synthesis, composition, and pharmacokinetics.

Ever Pharma's claim that it contains neurotrophic peptides in therapeutic quantities is likely false. HPLC and other evidence show Cerebrolysin is composed of amino acids, phosphates, and salt, along with some random protein fragments.

Ever Pharma's marketing materials for Cerebrolysin contain numerous scientific errors.

Many scientific papers on Cerebrolysin appear to have ties to its manufacturer, Ever Pharma, and sometimes those ties are not reported.

Ever Pharma's explanation of how the putative peptides in Cerebrolyin cross the blood-brain barrier does not make sense and flies in the face of scientific research which shows that most peptides do not cross the blood-brain barrier (including neurotrophic peptides like BDNF, CDNF, and GDNF).

Since neurotrophic factors are the proposed mechanism for Cerebrolysin's action, it is reasonable to doubt claims of Cerebrolysin's efficacy. Most scientific research is false. It may have a mild therapeutic effect in some contexts, but the research on this is shaky. It is likely safe to inject in small quantities, but is almost certainly a waste of money for anyone looking to improve their cognitive function.

Introduction

One of us (Dan) was recently exposed to Cerebrolysin at the Manifest conference in Berkeley, where a speaker spoke very highly about it and even passed around ampoules of it for the audience to inspect.

Dan then searched for Cerebrolysin on X and found a video by Bryan Johnson from May 23 that shows him injecting Cerebrolysin. Johnson describes it as a "new longevity therapy" that "fosters neuronal growth and repair which may improve memory."

Dan sent the video to Greg Fitzgerald, who is a 6th year neuroscience Ph.D. student at SUNY Albany. Greg is well-versed on the use of neurotrophic peptides for treating CNS disorders and was immediately skeptical and surprised he had not heard of it before. After Greg researched it, he felt a professional responsibility to write up his findings. He sent his writeup to Dan, who then extensively edited and expanded it.

Our critique covers three major topics: (1) sketchy marketing practices, (2) shoddy evidence base, and (3) implausible biological claims. But first, it's interesting to understand the history of this strange substance.

The long history of Cerebrolysin

To our knowledge, the "secret history" of Cerebrolysin has not been illuminated anywhere to date.

Cerebrolysin was invented by the Austrian psychiatrist and neurologist Gerhart Harrer (1917 - 2011), who started usin...