EHA 2016

Safety and efficacy of imatinib generics

Prof Tomasz Sacha - Jagiellonian University, Krakow, Poland

I will present the data coming from the Polish registry of imatinib generics. The branded generics has expired, the patent for branded generics has expired in December 2013 and starting from June 1st 2014 we are facing the imatinib generics in Poland. So we decided to establish the registry for just recording the data of effectiveness and of safety of generics. We realised that we will have about twelve preparations available on the market so therefore we thought it would be reasonable to test the hypothesis that generics are equally good, or maybe not, in our patients.

How did you go about testing that?

We have data starting from the first observation, from June 2014, and it seems that those generics are working very well. They are just compared for the ability to achieve early molecular response, the response after six months and optimal response after twelve months of using the generics and they are equally good. They have quite a good tolerability profile, however there are some differences between preparations that we have available. At the moment we have four preparations available on the market and two companies are taking the majority of the market of Polish imatinib generics.

You mentioned that they are equally efficacious, what about the safety profile?

Yes, they seem to be safe because we didn’t notice any increase of the switching grade between the first generation TKIs, imatinib, and the second generation TKIs. So they are comparable to the other data we have from the past from the literature. We didn’t observe any increase of number of losses of responses. So the CCOIR of patients that were switched from original branded to imatinib to generics is less than 1% and MMR loss is equally around 1-2%. We did observe some losses in very deep molecular response, meaning MR 4.5 which is around 4% but this is still acceptable and we cannot see any adverse effect of administering imatinib generics in our patients.

You mentioned the patients, how were they selected for the trial and were they made available to switch if they had any…?

Yes, this is not a trial, this is the registry. So we were trying to register all patients in Poland just switched from branded imatinib to generic imatinib. So the idea was to have as complete picture as it is possible. We have at the moment nearly 900 records, I will report on 726 records in this conference. So we have 16 centres participating in the project. Of course this does not cover all patients in Poland but that was the idea and I have the impression that probably 90% of patients that are treated with imatinib in Poland, they are covered by the registry. Because the registry is divided into two groups, the first is the analysis of what happened to patients switched from branded imatinib to the generic imatinib and the second is dedicated to de novo recognised patients, that’s patients suffering from CML and they just started the treatment with generics of imatinib. The question was, the first question we posted within this project, was the quality of the molecular monitoring within the treatment of CML because in the past the treatment with imatinib branded was pretty much centralised in Poland and it was left in the hands of haematologists. At the moment, theoretically at least, all doctors are employees of the hospitals, they have a contract with national, they can perform the treatment of patients with CML. In reality they really send those patients to haematologists but that was the question if the compliance to ELN guidelines regarding the frequency of monitoring, molecular monitoring of the treatment, will decrease. In fact in the survey I performed in 2012 we have 69% of patients that were followed just according to ELN guidelines. At the moment this ratio dropped down to 53% so it still is not bad but we are a little bit worried about the frequency of molecular testing in those patients.

With the registry being able to put together all of the safety and the efficacy the only question left there is cost.

By law in Poland the cost of generics should not exceed 50% of the cost of the branded drug but due to the competition I mentioned that we did have twelve generics available on the market. The cost dropped down in the first tenders organised by Polish hospitals to 5% of the original medication. At the moment after one year when the majority of the market is taken by four pharma companies we could see that the price is a little bit higher but still it is about 5-10% of the original medication.

In conclusion can you think of any good reason why wider application of generics for imatinib shouldn’t go forward?

I think it’s economically reasonable. Polish patients have some doubts of the efficacy of those preparations because only bioavailability data were available at the time but after these years of observation we can assure the other patients that they are equally effective as branded imatinib and they are very, very good drugs.