Explained impact of diabetes medicine sitagliptin going out of patent

Explained impact of diabetes medicine sitagliptin going out of patent

With the diabetes medicine sitagliptin going out of patent, many pharmaceutical companies have jumped on the chance to market generic versions of the drug–a move likely to bring down the price of the medicine by at least a third, according to industry experts. With sitagliptin not prone to causing low blood sugar episodes and being backed by robust data, doctors believe many diabetics might switch over to it if it becomes cheaper.

Here is a look at what the drug is, and how lower prices will help the 77 million diabetics in India.

What is sitagliptin and how does it work?

Sitagliptin is a blood sugar-lowering drug. It was first in the category called gliptins, where a protein called DPP-4 is restrained by it, and this impacts the metabolic system so that the pancreas is prompted to increase insulin secretion and regulate sugar in the blood. Another medicine from the same category developed by the pharmaceutical company Novartis, called Vildagliptin, also went off patent late last year, resulting in a subsequent price drop.

“We have 14 years of experience with this drug and it is very reliable – it has a good glucose-lowering capability and not much side effects. We can give it to young persons as well as the old because the drug is not prone to causing hypoglycaemia which is very harmful in the old,” said Dr Anoop Misra, eminent diabetologist and executive director of Fortis C-DOC Hospital that specialises in endocrine diseases.

He said that four of ten patients are prescribed one of the gliptins, with sitagliptin being the most common one due to good data received on its efficacy over the years. The trials for the medicine have also shown that it does not have any negative impact on the heart. Dr Misra said: “Excellent trials have been done to show that it doesn’t harm the heart. For any diabetic drug, it is essential that it doesn’t harm the heart…better still if it can benefit the heart.”

Does it have any benefit over other categories of oral drugs?

It was the drug of choice for treating type-2 diabetes where the body cannot regulate the blood sugar levels because it either does not produce enough insulin or resists its impact. It was toppled by a new class of drugs called SGLT-2 inhibitors, also known as gliflozins, which prevent the re-absorption of glucose from the blood when it is filtered by the kidneys, thereby reducing the blood glucose levels.

“It was the blockbuster drug for diabetes till another type of drug came and overshadowed it. A new category of drugs, called SGLT-2 inhibitors, came in some years ago and it had a better effect on the heart and hence, is now used more frequently. The second thing that happened was teneligliptin (a drug from the same category) became available at a very low price. That is why the sitagliptin market was eaten up by the SGLT-2 inhibitors and teneligliptin,” said Dr Misra.

Although SGLT-2 inhibitors continue to be the best in the category, a lower price for sitagliptin will likely re-capture the market of teneligliptin. Dr Misra said: “The problem with teneligliptin is that it is without robust clinical data. So, if the price of sitagliptin is lowered, people who were using the other medicine because of price constraint will come back to sitagliptin and its sale will increase.”

“Another benefit is that it has almost no side effects. Some have a problem with hypoglycaemia (sugar level dropping too low), metformin has a major problem with gastro-intestinal side-effects, the new SGLT-2 inhibitors have a problem as far as urinary infections are concerned,” he added.

So now that the drug is off-patent, what is likely to happen?

With several companies likely to start making generic versions of the drug, the prices might reduce by a third of the current price–of more than Rs 20 per tablet. More than 50 companies with over 100 brands are likely to bring the drug to the market between July and August 2022, according to pharmaceutical market research firm AIOCD Awacs PharmaTrac. It said since vildagliptin and SGLT-2 inhibitor dapagliflozin went off-patent, there has been a shift towards these medicines.

Zydus Lifesciences has launched Sitaglyn and Siglyn, which are likely to cost 60 percent less than the originator or first version of the drug, the company said in a release. “The addition of Sitaglyn and Siglyn to our diabetes portfolio will give patients access to a world-class oral therapy to help people manage their diabetes better by making it more affordable,” said Dr Sharvil Patel, Managing Director of Zydus Lifesciences.

Glenmark Pharmaceuticals also announced eight fixed-dose combinations with sitagliptin with the brand name Sitazit. It was the first company to launch the generic version of vildagliptin that had started a price war. A company spokesperson from pharma company Dr Reddy’s Laboratories said: “We are launching sitagliptin under the brand name Stig. In keeping with our purpose of ‘Good Health Can’t Wait’, Dr Reddy’s Stig will be among the most affordably-priced options available to patients living with diabetes.”