CLINICAL AND RESEARCH INFORMATION

Over the last several years, Russian biochemists have been researching a special analogue of the di-peptide carnosine called n-acetylcarnosine or NAC which is claimed to be efficacious in the treatment of cataract. 

Recently NAC eye drops have become available in the UK and the treatment was discussed by a BUPA registered cataract surgeon on national television in December 2003. The hosting programme is running a six month treatment TV trial involving three patients with mild, moderate and severe cataract who were sent for ophthalmic verification prior to commencement of NAC. An extensive feature on the use of NAC in cataract treatment appeared in the Daily Mail's Good Health section on December 16th 2003 .   

Legal Status

NAC is not a medicine or medical device and as such falls under the General Consumer Safety Legislation. It does not have a CE Mark at this stage since it is not required. N-acetylcarnosine 1% can be labelled as an inactive ingredient since it is not classified as a drug.  As incredible as it sounds, this alternative treatment to surgery does look promising especially when combined with lutein as a dietary supplement.  However it is simply too early to tell whether NAC is efficacious in all types of cataract.

Clinical trials

Presently the NAC eye drop treatment  has been applied to around one thousand patients with senile cataract in China and Russia (those countries are home to the principal researchers behind the work) and clear evidence is emerging that NAC eye-drops are a safe, effective treatment.

Chinese and Russian researchers have studied cataract-preventive nutrients for nearly a decade. A Chinese study done by A.M. Wang in 1999, used 96 patients aged 60 years or older having senile cataracts of various degrees of maturity with the duration of the disease from 2 to 21 years. Patients instilled one to two drops of the carnosine-containing solution in each eye three to four times each day for a period of treatment ranging from three to six months. The level of eyesight improvement and the change of lens transparency were considered as an evaluation index of the curative effect of carnosine. The result showed that carnosine gives a pronounced effect on primary senile cataracts, the effective rate being 100%. For mature senile cataracts, the effect rate was 80%.

The Russians most recent contribution was published in 2002 in the journal Drugs Research and Development. In two separate studies, they applied a one percent solution of N-acetyl-carnosine to the affected eyes of cataract patients twice a day. Only patients with mild cataracts-not anticipated to require surgery within the next two years-in one or both eyes were selected to participate. A matched control group received placebo drops, and another small matched group received no drops at all. The first study lasted six months, while the second on 49 patients continued for a total of 24 months. Tests of visual acuity and glare sensitivity were administered every two months in the first study and every six in the second.

After six months, 90% of eyes treated with N-acetyl-carnosine showed improvements in visual acuity ranging from 7% to 100%. Glare sensitivity improved from 27% to 100% in 88.9% of carnosine recipients, and retro-illumination image analysis (a measurement of lens transmission) improved in 41.5% of treated eyes. Lens examination revealed fewer areas of lens opacity in the posterior subcapsular region. No worsening of vision was found in the eyes treated with N-acetylcarnosine whereas in the placebo group, there was little change in vision at 6 months and a gradual deterioration from 12 to 24 months.

Moreover, this study also showed that at 24 months the NAC treated group, (who already had significant improvement to the quality of their eyesight), sustained these results with continued use of the NAC eye-drops. Importantly, it was also noted that there were no side effects in any of the cases.

CLICK HERE RESEARCH