Lantus is the brand name of the insulin glargine sold by Sanofi worldwide. Profits are shared with Novo Nordisk because of a lawsuit Novo Nordisk filed some years ago saying that the patent belongs to them.
In India, insulin glargine is also available under the name Basalog, sold by Biocon.
In India, the price of insulin glargine has therefore dropped in the last few years, but in the US the price increased about 10% over the last year (the company's reasoning seems to be that they can get away with it).
Sanofi advertises Lantus as lasting 24 hours for a flat basal profile. This is not much backed up by their own data, which shows that:
-in the person that it lasted the least amount of time for, there was no glargine detectable in the person's blood 10 hours after injection
-they did not measure levels of glargine in the blood MORE than 24 hours after injection, only up to 24 hours. In most people, there was still glargine active at 24 hours. The half life of Lantus injected subcutaneously in lab animals is about 30 hours and there is some evidence that it is about that length in humans as well. In this study where glargine was made radioactive and injected into type 2 diabetics, the time it took for half the glargine to leave the body was 26.3 hours. http://www.ncbi.nlm.nih.gov/pubmed/12931275
Lantus does not reduce A1cs in any studies by any statistically significant amount as compared to NPH or Levemir. Its strongest point is that it reduces the risk of hypoglycemia at night compared to NPH- and that it does pretty dramatically. It also lends itself to allowing a basal bolus system of injection when used with a fast acting insulin.
Lantus is currently the most prescribed insulin in the United States. Personally, I don't think it deserves the honor, given that most of the prescriptions are in people with type 2 diabetes who do not use any other insulin and would probably get as good or better control with once daily injections of NPH.
One large and well publicized study of Lantus users showed a higher risk of breast cancer in Lantus users as compared to users of other insulins (the risk was only in people using Lantus without another insulin). No other study has found the same results.
Glargine insulin is made by genetically modified escherichia coli bacteria for Sanofi, and by a genetically modified pichia pastoris yeast for Biocon.