HAMA explained

MENSCHI WAS TESTED TODAY TO SEE IF HE HAS DEVELOPED "HAMA"

(To learn more about HAMA read below -From MSK website)

What is HAMA?HAMA stands for "human anti-mouse antibodies." HAMA measures how strongly the body's immune system is reacting to 3F8. 3F8, like most monoclonal antibodies, comes from the white blood cells of a mouse. This means that 3F8 looks different from a human antibody, and thus patients will eventually form antibodies (HAMA) against 3F8. Once a patient has developed HAMA, 3F8 treatments no longer effective because the HAMA blocks the 3F8 from getting to neuroblastoma cells. If the patient has received the desired amount of 3F8 (see next question for further information) by the time HAMA has developed, then treatment with 3F8 will be discontinued. However, if the patient has not yet received the desired amount, it is possible that HAMA may recede, and in that case we can resume 3F8 treatments. We conduct a blood test for HAMA usually one to two weeks after each round of 3F8 infusions. Patients with HAMA usually do not have pain or other side effects from 3F8 treatment.

Is HAMA good or bad?HAMA is a positive sign in that it may mean the patient is developing an immune response against the neuroblastoma. However, when HAMA develops before the patient has received the usual 400 mg/m2 of 3F8 (two to four cycles), it may interrupt treatment. (As noted above, once HAMA is present, the 3F8 treatment is no longer effective.) Once HAMA has receded, treatment can resume. Most patients who have received chemotherapy only a short time before 3F8 treatment do not produce HAMA because part of their immune system is too suppressed. In these cases, 3F8 treatment will usually continue for up to two years. The aim of our protocols is to give repeated treatments with 3F8 until HAMA is made, because we believe that approach yields the best chances for cure. We continue to study HAMA to get a better understanding of how it may hurt or benefit patients in the long term.