Un combat sanglant

Tiens, c’est marrant, mais ce tweet de theheart.org vient juste de tomber:

Il s’agit d’un commentaire d’un abstract qui semble montrer que le dabigatran « dans la vraie vie » n’est pas forcément facile à manier.

Dosage of dabigatran was 150 mg twice daily in all patients except for two who received 75 mg twice daily. The mean treatment time for dabigatran was 3.9 months. During the warfarin treatment period, time in therapeutic range was 70%.

Results showed that during the warfarin treatment period, there was one event (0.88%) necessitating drug discontinuation—the patient was hospitalized because of a high INR. This compared with 13 events (11.5%) in the dabigatran treatment period. These included one treatment-related death (GI bleed), four other bleeding episodes (two GI bleeds, one rectus sheath hemorrhage, one intracranial hemorrhage associated with trauma), one deep venous thrombosis, one atrial thrombus, one transient ischemic attack, one skin rash, and four patients with GI symptoms.

These adverse reactions were more common in older patients and in females. The mean age of patients experiencing complications on dabigatran was 73.4 years, compared with 66.5 years for the whole population. And women represented 29% of the overall population, but 71% of patients with complications.

On retrouve toujours les mêmes problèmes qu’en Nouvelle-Zélande, c’est à dire une prescription trop enthousiaste chez des patients largement moins surveillés que dans les essais cliniques: patients âgés, faibles poids (femmes?), dosages non adaptés (110mg vs 150mg)…

L’âge des patients qui ont plus de problèmes (73.4 ans) n’est pourtant pas beaucoup supérieur à celui des patients de RE-LY (D110:71.4±8.6, D150:71.5±8.8, W:71.6±8.6)…

L’auteur de l’abstract pointe le souci de surveillance:

« The problem with dabigatran is that it has been presented as a ‘fire-and-forget’ medicine. That is, the doctor can write a prescription and not think about it again. But anticoagulation is not like that. Just because patients on dabigatran don’t need to have regular INR measurements doesn’t mean they don’t need monitoring. »

L’auteur principal de RE-LY se défend comme il peut:

« These experiences in a highly selected group of patients are vastly different from the results with dabigatran in the randomized RE-LY trial and from the much lower rate of spontaneous worldwide reports on side effects during the more than 700 000 patient-years of treatment with dabigatran in real life over the past years. Still, these observations emphasize that the risk of side effects with dabigatran is largest in elderly patients and in patients with reduced renal function. In contrast to what was used in the patients presented in the poster, such patients should be prescribed the lower dabigatran 110-mg twice-daily dose, and it is very unfortunate that this dose is unavailable in some countries. The presented experiences also emphasize the need for other alternative oral anticoagulants, as it is rather tricky to switch from warfarin and back, but considerably simpler to switch between the new oral anticoagulants if needed because of side effects or other problems with tolerance or compliance. »

En gros, la vraie vie n’est pas encore la vraie vie, et il faut faire attention à nos prescriptions.

Bon, ok, rien de bien neuf sous le soleil.

Détail rigolo, pour qui roule l’auteur de l’abstract?

Rivaroxaban? Apixaban?

Bah pas du tout, pour un labo qui commercialise entre autres des kits d’INR ou des algorithmes de gestion d’INR:

• Alere®

• Standing Stone®
  

J’ai d’ailleurs reçu le 4 mai un gentil courrier d’une boite travaillant pour Alere® me faisant part de l’existence de cet abstract (je l’avais balancé sans le lire):

Le monde de l’anticoagulation est sans pitié: Père, gardez-vous à droite ! — Père, gardez-vous à gauche ! (Philippe le Hardi, Poitiers 19/09/1356, ça a aussi beaucoup saigné ce jour là…)