It was criticized that I selected the study data on Ocrelizumab as my personal highlight of the last ECTRIMS meeting and did not dedicate a single line to the data on Minocycline. I would like to make up for this – because the study on the effect of Minocycline in patients with the first demyelinating event presented in Barcelona is indeed interesting, albeit not groundbreaking, as some of the commentators claim.
For those who do not know what this is about, I would like to briefly summarize the study: A group of 12 Canadian MS centers tested the effect of Minocycline in patients with a first relapse event and risk of transitioning to a clinically certain MS between 2008 and 2013. It was investigated how many percent of the included patients develop a clinically certain MS during the observation period, i.e., experience another relapse. For this, 142 patients aged between 18 – 60 years were included in the study within 180 days after the first relapse event and treated either with Minocycline (72 patients) or with placebo (70 patients) and monitored at regular intervals over two years by a neurological examination and MRI recordings.
The study showed that after 6 months, 34% of the patients treated with Minocycline and 61% of the patients treated with placebo had a second relapse and thus the diagnosis of “clinically certain MS” could be made. This result corresponds to a relative risk reduction of 44.6% in favor of Minocycline and is statistically significant (probability of error 0.1%). This is a good result, although it must also be mentioned that the difference between Minocycline and placebo was no longer significant after 2 years of observation.
What kind of substance is Minocycline?
Minocycline is a semi-synthetic tetracycline – an antibiotic that has been used for many years, especially in the treatment of severe acne and rosacea, and has a relatively favorable side effect profile. After tetracycline also represents the standard treatment for Lyme disease infections (esp. Erythema chronicum migrans), the study results on Minocycline and MS were immediately interpreted in the direction that there is now clear evidence that MS is caused by an infection with Borrelia. This is pretty nonsense.
In addition to its bacteriostatic activity, Minocycline also has a variety of immunomodulatory and neuroprotective effects (among other things, Minocycline inhibits so-called matrix metalloproteinases, which are important for T-cell transmigration into the brain). Because of these properties, the effect of Minocycline has been studied in the last few decades in a large number of neuroinflammatory and neurodegenerative diseases and has led to interesting results. Therefore, the now published study is not too much of a surprise for insiders.
As for the effect strength of Minocycline, however, there are still some questions. For one, the study was only conducted on a small number of patients, and it is known that the early phase of the disease is very accessible to anti-inflammatory concepts. Interferons achieve a relative risk reduction for the transition to a clinically certain MS (over an observation period of 2 years) between 50 and 60% in this phase of the disease already at low dosages. Therefore, the claim is wrong that the results of Minocycline are better than those of the “established drugs of the pharmaceutical industry”.
Before its value for the therapy of MS can be finally evaluated, Minocycline would also have to show positive study results in the treatment of relapsing MS. Therefore, the results on Minocycline should be watched with interest for now and no hasty conclusions should be drawn.
What is correct, however, is the annoyance of some commentators that the further development of substances like Minocycline is not sufficiently promoted. A drug like Minocycline, which has been on the market for many years and no longer has patent protection, is uninteresting for the pharmaceutical industry. Unfortunately, at least in Germany, the pharmaceutical industry is the only carrier of drug development and drug approval – the state has withdrawn from this. Scientists in academic institutions in Germany (and Europe) ultimately do not have sufficient funds to bring drugs to approval independently of the pharmaceutical industry. Therefore, it would be time to exert political influence and finance academic research in Germany/Europe better.
