Levothyrox : Merck is explained

ALLILI/SIPA

Published the 13.09.2017 at 18: 40

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Lévothyroxindustrie pharmaceutiqueeffets adverse

The change of formula of the Levothyrox is in difficulty in France. Thousands of patients complain of side effects related to the new formula of this treatment for the thyroid disorders. The health authorities want to be reassuring : these effects will fade, they are related to the profile of the drug, the dose should be mapped and whose variations can cause these adverse effects.

It does not prevent. A complaint against X was filed, a petition calling for the return to the old formula, amended by the laboratory on request of the MSNA (national security agency of the drug), in order to improve the stability of the drug. Looks towards the lab, accused of not having sufficiently warned, in advance, informed. In Belgium, for example, the tests related to the new formula have been carried out on voluntary patients. They have identified all the side effects and the profiles of the patients involved. Why France did not follow this path ? Valerie Leto, a pharmacist responsible for Merck, returns on these questions.

Were you expecting an increase in adverse effects related to the new formula ?

Valerie Leto : Yes, but not to this extent. We had identified a specific population of patients, who may experience side effects with the transition to the new formula. These are patients who have already had difficulty in obtaining a balance of the thyroid. We have informed prescribers and pharmacists of the change of formula, indicating that for some patients, it will be important to perform assays TSH in order to check that they are not in hypothyroidism or hyperthyroidism.

But we were not expecting to have as much lift. There may be a media effect. However, reports of adverse events that we collect relate to the expected symptoms associated with an imbalance of the thyroid. No side effect is described out of this framework. Moreover, tests have been conducted by our laboratory, they will validate the compliance of the drug. The product that we put on the market is a product of quality. Another study conducted by the MSNA is being on the tablets in order to check the quality and compare the results with ours.

Why not have attempted to evaluate these adverse effects upstream, knowing that they would occur ?

Valerie Leto : We carried out, under request of the MSNA, two types of analyses : tests of stability of the drug accelerated for six months at 40 degrees, and in actual conditions during two years), and tests of bioequivalence. The agency has not required the addition of extra tests, because this is not the procedure during a change of excipients.

We do not believe that tests conducted on volunteer patients were enabled to better assess the side effects. We probably would have seen signs of hypothyroidism and hyperthyroidism, but these results would have been difficult to interpret, since there is a high variability from one individual to another… In general, we do not conduct studies on patients after a medicine is marketed, in any case, we aren’t asked. I know that this has been done in Belgium by Takeda, but the laboratory has undertaken this type of testing this because the bioequivalence studies that he had first conducted did not demonstrate equivalence between the two formulas.

Why not have informed the patient through the leaflet that they could have unwanted effects ?

Valerie Leto : When we launched the product, the analysis that we have done, is that he had to go by the health professionals to disseminate information and not directly by patients. This decision was motivated by the fact that this is not the patient to change his dosage, but the health professional to decide, to analyze the symptoms may not be due to the Levothyrox. The important thing, therefore, was that the doctor and the pharmacist have the information to watch pathology in its entirety. We have also modified the design of the boxes so that there is no confusion.

The minister has announced the creation of a working group to see what has happened, what could have been better done, to learn the lessons. We’ll be exhibiting, of course, if we are asked. We also analyze internal communication and management around the change of formula. Is this a proactive type of communication in the boxes, as in Belgium, would have been able to better meet the needs of patients ? It is an analysis that we are conducting.

The european procedure is compromised by the problems encountered in France ?

Valerie Leto : A harmonization process has indeed been launched with the EMA (European medicines Agency) so that the new formula is available in other european countries, where we find the old formula. The application is running and I have no information about a possible brake to the procedure. The situation is quite different in the other countries of Europe because they have alternatives in Levothyrox.