Januvia Revisited - Results of my Own Trial of This New Drug

UPDATE (April 2, 2013): Before you take Byetta, Victoza, Onglyza, or Januvia please read about the new research that shows that they, and probably all incretin drugs, cause severely abnormal cell growth in the pancreas and precancerous tumors. You'll find that information HERE.

Original Post:

Januvia is a new drug which works on the incretin hormone system in a different way from Byetta. While Byetta provides a synthetic version of GLP-1, Januvia allows GLP-1 secreted by your body naturally to rise to higher than normal levels by inhibiting the action of DPP-4, an enzyme which removes GLP-1 and another hormone, GIP, from the body.

I was initially skeptical that Januvia was worth taking, given its very high expense ($5 a pill) and the study data that the manufacturer supplied with the press releases which made it sound like it produced very little improvement in blood sugar overall--the study data showed that in people whose A1c was 8%, Januvia decreased the A1c by a measly .6%--bringing it to a level significantly higher than even the dangerously high 7% recommended by the ADA. Added to Metformin or Avandia, the studies found Januvia got only about half of patients near 7%.

But in reading initial reports online from people trying Januvia I noticed an interesting pattern. The drug either worked very well for them or not at all. This made me rethink the statistics in the Prescribing Information and wonder if that .6% decrease in A1c was the result of averaging the results of many people who experienced a 0% decrease in A1c with a few who achieved a much larger decrease.

Having noticed how many people with health histories similar to my own were doing extremely well on Byetta, I'd been wanting to try an incretin hormone drug, but had avoided Byetta because of the possibility of developing antibodies and a disinclination to be nauseated. I got some samples of Januvia from my endocrinologist early in January and started taking it. I've been on it 11 days now.

Initial results have been extremely impressive. I stopped taking my low dose insulin and an getting almost the same normal blood sugars with Januvia as I had been with low dose insulin--without having to worry about hypos. I find I need to eat some carbohydrate with each meal to stimulate the release of insulin while taking Januvia, but once the insulin is secreted, since it is being secreted in a normal physiological way it works quickly. I found myself at 99 mg/dl (5.5 mmol/L) one hour after eating 30 grams of pastry several times and was in the very normal 80s an hour later!

I found that in my body a carb intake of 20-30 grams was handled very well by Januvia. Above that level it took three hours to get to a fasting level of 85 mg/dl (4.7 mmol/L) not two, so at this level insulin did a better job. But the ease of use of the Januvia, a once a day pill, is a huge plus compared to insulin. Keep in mind when reading this that I have a kind of diabetes where I am not insulin resistant. So tiny doses of supplemental insulin work very well for me.

The main side effect I have noticed so far is a lowered blood pressure which occasionally makes me dizzy. (I am not on any BP meds.) Because the drug is so new and is suppressing a hormone (DPP4) which is used by many other organs in the body, including the immune system, I do have a serious concern about what its long term side effects might be, in particular whether it might promote cancer. DPP4 is also suppressed in melanoma cells and those of other tumors. Rats fed a very high dose of Januvia (60 times the normal amount) did develop liver cancer, though mice did not. This is not trivial and only a lot of time with reveal the impact of DPP4 suppression on people.

Despite my good results on Januvia, it may not be the best choice for most insulin resistant people with Type 2 diabetes. The reports from people who had been getting good results from Byetta whose doctors moved them to Januvia are not encouraging. It does not appear to work for most of them--possibly because they have developed antibodies to their body's own GLP-1, or perhaps because they don't make enough GLP-1 to do the job. Januvia requires that your body be making GLP-1 on its own. I am very insulin sensitive, so Januvia doesn't need to stimulate my body to make much insulin. If you need more insulin, you may not get good results with Januvia.

Also Januvia is being described as being weight-neutral (i.e. not causing weight gain) based on two studies, one of which showed a slight gain of weight in those taking the drug. This might make it a worse choice for many people with Type 2 diabetes than Byetta as Byetta, when it works, causes weight loss.

For the time being, it looks like Byetta would be a much better choice for an incretin hormone-based treatment for Type 2s who need to lose weight, though Januvia might be an ideal drug for normal weight people with non-autoimmune diabetes whose diabetes like mine is characterized by a very high post-meal blood sugar and near normal fasting blood sugars. It might also be a good drug for people with pre-diabetes--if their insurance will pay for it. The cost issue is a tough one since Januvia is so expensive and so new that many plans won't pay for it.