A medical active ingredient is not yet a drug. The active ingredient must first be combined with auxiliary substances into a specific dosage form, e.g. as a tablet, as a juice or as an injection. The preparation with auxiliary substances also influences the concentration and the duration of stay of the medical active substance in the body. The science of composition and preparation (production) of drugs is known as galenics. The term goes back to the Greek doctor Galenos (Galen) of Pergamon. He was one of the most important doctors of antiquity, who practiced in the second century after Christ. The dosage form (galenics) of drugs also plays an increasingly important role in modern MS therapy against the backdrop of the multitude of MS drugs. It can have a decisive influence on the choice of therapy. Because for many patients (of course in addition to effectiveness) the comfort of therapy and compatibility with professional life are now an important decision factor.
Dosage form decision factor in MS therapy choice
The approval of Ofatumumab (Kesimpta®) therefore brings movement to the MS market. Ofatumumab is a monoclonal antibody against the surface molecule CD20. Like Ocrelizumab (Ocrevus®) and Rituximab (off label for MS), it leads to the removal (depletion) of B-lymphocytes and thus to effective control of inflammatory activity (especially in early phases of the disease). Unlike Ocrelizumab and Rituximab, which are administered as infusions every six months and require approximately 4-6 hours of presence in a (specialized neurologist’s) practice, Ofatumumab can be administered as a subcutaneous injection, which can be performed in a few minutes. In addition, the technical information allows subcutaneous self-injection, if the first injections were administered smoothly under the supervision of professional staff. This is certainly a step forward for certain patient groups. Even if you will consider whether you would rather inject yourself subcutaneously once a month (as is the dosage form of Ofatumumab) or come to the practice once every six months for 4 – 6 hour infusion therapy (as is the dosage form of Ocrelizumab). But I think that this choice alone in a highly effective MS therapy is a step forward for MS patients.
However, it is still somewhat unclear to what extent the “do-it-yourself” approach is really being implemented. I have to say that I was a bit surprised myself at how well the subcutaneous injection was tolerated in the clinical trials. There were no severe injection reactions and premedication (e.g. with steroids) before administration of Ofatumumab is not recommended. This is surprising given the effort we put into premedication with Ocrelizumab and Rituximab infusions. Therefore, there may be doctors who initially recommend self-injection cautiously and would like to observe patients even after a subcutaneous injection. The handling of Ofatumumab will probably adjust with increasing practical experience.
Changes in galenics of existing products
The innovations in the galenics of highly effective MS drugs naturally also influence other pharmaceutical companies to change the galenics of their products. So it’s no wonder that recently, in addition to infusion, the subcutaneous administration of Natalizumab (Tysabri®) was approved. Natalizumab is also a highly effective and well-tolerated MS drug. It had to be infused every 4 – 6 weeks. In contrast to infusions with B-cell depleting therapies, Natalizumab infusion is less complicated. On average, patients spend 1 – 2 hours in the practice for this. However, it must be noted that the availability of subcutaneous Natalizumab pre-filled syringes (so far) does not generate a big advantage. For one thing, the technical information currently excludes a “do-it-yourself” approach, the subcutaneous injection must be administered by medical professionals. In addition, one pre-filled syringe contains 150 mg, but 300 mg should be given, so 2 x prick. After the first six injections, monitoring for one hour is required, which can then be shortened at the discretion of the doctor. Despite the restrictions, it must be acknowledged that the subcutaneous injection of Natalizumab at least reduces the effort for practices – and of course, with good tolerability, also a significant time saving for the patient.
We can now look forward to seeing how the new galenic offers are received by MS patients, but also by prescribing neurologists.
