What is the risk of infection associated with BCMA directed therapies?

What is the risk of infection associated with BCMA directed therapies? Why does this risk exist? 
So what are the risks of BCMA approaches or BCMA treatments? BCMA is a marker on the plasma cells. and we should we see that, you know, the more aggressive or the more progressive the myeloma, the more BCMA we have on those plasma cells. and we, have seen a lot of good responses to, BCMA based or targeted treatment. 
Now, unfortunately, almost all myeloma treatments attack all plasma cells. Plasma cells in our body are cells that help us fight infections. So we're giving a treatment that will not differentiate between a bad plasma cell and a good plasma cell. It will kill both. We end up in a situation where we don't have a good defense mechanism, also for the new bispecific antibodies or for the CAR-Ts with the Car-T, we give large doses of chemotherapy, we kill the lymphocytes, all of them. So we can create a space for the new lymphocytes for bispecific. We're we're grabbing those lymphocytes in one hand and the plasma cells in other hand and put them both next to each other. Means this lymphocyte is already occupied with another job. And they might forgo or overlook infections.This is very important when we start treatment with BCMA targeted, agents. To me, whether it's Car-T or whether it's a bispecific antibody, prophylactic antibiotics are very important. Actually. We have seen we call it PJP pneumonia. And you don't have to remember the name. It's an opportunistic infection. We see that those cases of pneumonia, tend to be higher in patients who don't get prophylaxis. And those are, microbes that are in the air everywhere. We cannot, you know, avoid them. Usually they don't cause infection. Why? Because our lymphocytes always stop them, on the border. But, after starting BCMA treatment, as we mentioned, the whole immune system is occupied. Then those germs or those microbes can cause, problems and pneumonias giving, bactrim giving, pentamidine among other options.is very important for those patients. in addition, we all know all multiple myeloma patients should know this by now. any treatment or most of the majority of the treatments go hand in hand with acyclovir to protect from shingles. very few exceptions throughout the treatment. course, where we don't use acyclovir. So the default is acyclovir all the time. and if we have a pancytopenia, we always give antibiotics and antifungal those to protect from actual germs and day to day, kind of activity. once the pancytopenia resolves, then we continue with, prophylaxis, acyclovir and, for example, and BCMA targeted treatment. something against PJP pneumonia. So, the other role for plasma cells is to produce IgGs or IgA or IgM immunoglobulins. Once we, if we, killed good plasma cells, then we will not have IgGs, IGA, IgM and levels high enough in the blood. The most important of those is the IgG, levels, which is, they can protect us from infections. after BCMA based treatment. With such good, effective treatments, we wipe out everything in terms of plasma cells, it's important to replace, IgG levels with IVIG. we do it, once a month. after Car-T treatment, I like to monitor the IgG levels in the, for the patient in the blood and make sure it's more than 400. the cutoff is also variable. for bispecific antibodies. I like to keep going with IVIg, regardless of the IgG level in the blood, just to make sure we, support the patient, from infection. Infections with BCMA therapies should be broken down into the mechanism of action of the BCMA therapy, whether it's a Car-T bispecific or an antibody drug conjugate. Probably from least to highest would be the antibody drug conjugate is the least, followed by the Car-T, followed by the bispecific. And part of that has to do with the fact that bispecifics are repeatedly targeting the antigen as opposed to Car-Ts are done once, and then the antibody drug conjugates seem to be gentler. But the most, severe case would be the BCMA bispecifics, which have a rate of infections of around 80% and about 55% are high grade infections. Grade three or higher.