Biotech Catalyst Play: Actinium Pharmaceuticals Inc (NYSEMKT:ATNM)

On June 12, Dr. Rajneesh Nath, a Principal Investigator and Director of the Bone Marrow Transplant and Acute Leukemia Program at MD Anderson will host a conference call alongside execs from development stage biotechnology company Actinium Pharmaceuticals Inc (NYSEMKT:ATNM). The call is set up to update shareholders and wider markets as to the progress of the company's lead development program – an investigation into the efficacy and safety of an asset called Iomab-B.Actinium ran up early this year but has essentially traded flat since the start of February. If the update that hits press on June 12 is supportive of an efficacy thesis for Iomab-B, however, this is going to change quickly.Here's what we're looking for from the conference call as a bullish signal.So, the drug is called Iomab-B as we've mentioned and it's a combination of what's called BC8 (a monoclonal antibody) and a radioactive isotope called I-131. The monoclonal antibody is able to target an antigen called CD45. More on this in a minute. Actinium is going after patients over age 55 with relapsed or refractory acute myeloid leukemia (AML) who are about to undergo a bone marrow transplant. With these patients, the goal is to kill as many cancer cells as possible ahead of a transplant so as to increase the chances of the new marrow producing cancer free blood cells. Right now, standard of care is chemotherapy and radiation. As most reading will know, however, this SOC is incredibly toxic and is limited by this toxicity. The reason it's so toxic is that it's not selective – it just goes in and kills cells unchecked. The idea is to destroy cells and hope that the treatment destroys all the cancer cells before it kills enough cells to kill the patient.As mentioned above, Iomab-B is able to target an antigen called CD45. This antigen is expressed to a high degree by the cancerous blood cells associated with AML, and not by (many) other cells. When the drug recognizes the antigen it links up to the cell expressing it and its radioactive isotope becomes activated, killing the cell to which it's linked. This allows the drug to target cancer cells and not healthy cells, meaning the treatment can be used at higher concentrations without being toxic and – by proxy – can get rid of a higher number of cancer cells ahead of an AML patient's BMT.It's in a phase III study right now in the above discussed population, with the study set up to compare the asset to SOC therapies (we won't list them, but it's basically a list of your industry standard chemo agents). The company hopes to enroll 150 people, give them Iomab-B or control, have them undergo a BMT and then monitor them for twelve months to see if the cancer comes back.So what are we looking for from the call?Well, we don't know how far into enrollment the company is right now but we're assuming that phase of the trial is complete (it's set to wrap up in April next year, so with a twelve month follow up the last patient needed to have undergone BMT a couple of months ago).As such, we're looking to see how many of the patients that have been dosed and had a transplant are in line for meeting the primary endpoint – achieving what's called a durable complete remission, which is defined as a complete response lasting 180 days or more. There's a good chance some of the patients will have already hit against this endpoint (more than a year has passed since dosing started) and so we'd love to get some insight into how many, and how this number compares to control.So, to summarize – the catalyst is anything that points to Iomab-B treatment translating to durable complete remission in the AML patients on the active arm of the trial. We'll be listening in and we'll put forward our interpretation of the data shortly thereafter.Catalyst date: June 12.Here's the trial listing page for anyone wanting to brush up on the protocol ahead of the call.We will be updating our subscribers as soon as we know more. For the latest updates on ATNM, sign up below!Disclosure: We have no position in ATNM and have not been compensated for this article.