Mabthera for Multiple Sclerosis
My office for today. Worked during the infusion.
Here in the Nordics, when a patient is at risk for PML and can no longer continue Tysabri, the next line in medication is MabThera, at least that’s what my neurologist said.
Manufactured by Roche, MabThera (rituximab) is actually used to treat non-Hodgkin’s lymphoma (NHL) and chronic lymphocytic leukaemia (CLL). MabThera is a chimeric monoclonal antibody therapy that targets the protein CD20 on the surface of B-cells (a type of lymphocyte that plays a key role in immune response) and causes select mature B-cells to self-destruct. CD20 plays an important role in helping B-cells function in the immune response, so inhibiting CD20 depletes B-cells and limits their proinflammatory function.
Although not officially endorsed for Multiple Sclerosis, the effectiveness of rituximab in people with MS was tested in Phase 2 and 2/3 studies. A 48-week, randomized, placebo-controlled Phase 2 study included 104 people with relapsing-remitting MS (RRMS) who were randomly assigned to receive intravenous rituximab 1000 mg (given as 2 infusions separated by 2 weeks) (n=69) or placebo (n=35). Rituximab resulted in a 91% reduction in gadolinium (Gd)-enhancing lesions compared with placebo. Additionally, a significantly lower percentage of people who received rituximab (20%) had relapses compared with those who received placebo (40%). You can read more about the study here.
MabThera is a sterile, clear, colourless, preservative-free liquid concentrate for intravenous (IV) administration after dilution. It is supplied at a concentration of 10 mg/mL in either 100 mg (10 mL) or 500 mg (50 mL) single-use vials. MabThera is formulated in sodium citrate, polysorbate 80, sodium chloride, sodium hydroxide, hydrochloric acid and water for injection. The recommended initial rate of IV infusion for MabThera is 50 mg/hr. After the first 30 minutes, it can be escalated in 50 mg/hr increments every 30 minutes, to a maximum of 400 mg/hr. Subsequent doses can be infused at an initial rate of 100 mg/hr, and increased by 100 mg/hr increments at 30-minute intervals, to a maximum of 400 mg/hr.
My Experience with Mabthera
I was asked to arrive at the Danderyds Sjukhus at 8:00 in the morning so I can take my pre-medication. My first attempt was actually a week before, where I took the standard dose of pre-medications. These include 2 Alvedon 500 mg tablets, 1 Cetirizine 10 mg tablet, and 8 Prednisone 5 mg tablets, dissolved in water. I had to wait for one hour for the meds to kick in.However, after the first hour of infusion where the drip was only at the slow rate of 50 mg/hr, I developed a severe allergic reaction. My scalp and ears were on fire and I wanted to pull my hair out! I was itching so bad I was surprised I had no blood on my nails My nose started running and my throat started swelling, making it hard to swallow. We had to stop immediately and rescheduled me a week after. Needless to say, I was very appointed. I had wanted to continue after the side effects subsided but the doctor advised otherwise.
The second attempt was today, and it went remarkably well, if not boring. The difference this time was that I had to take double the dose of the pre-medications.
An infusion takes about 6 hours, from the pre-medication to the actual infusion, and the one-hour observation period after. They checked my vitals and increased the flow rate every 30 minutes. My blood pressure was normal throughout and it fluctuated minimally, but normal nonetheless. My pulse was fast though, and it ranged from 80 bpm to 108 bpm. This reminded me to have this looked at when I get home to the Philippines.
Since I have a port-a-cath, it makes moving about very convenient. I don’t have to walk like a zombie, always having to look after the IV line on the arm. It also allows me to work properly. I brought my laptop and was typing away, ignoring the groggy feeling pressing on as the hours went by.
I’ve been really anxious about this as I wanted to get it over and done with. I am traveling and going home to the Philippines for 5 months and needed some protection that will last a while. For the treatment of multiple sclerosis, MabThera is given every 6 months. This is a huge deal for me as Tysabri, while awesome, sort of hampered on my travel planning. I needed to be tied to a hospital every month. With MabThera, it allows me to be more spontaneous and free.