Friday, May 16, 2014

A Measles Vaccine Kills Cancer?

     They hook you up and then, five minutes into the hour-long process, you get a terrible headache. Two hours later, you start shaking and vomiting and your temperature hits 105 degrees. That doesn't sound like too much fun. But what if this was all you had to endure in order to get rid of your cancer?
On May 14th, 2014 the Mayo Clinic released a news statement on the successful result of phase 1 of a clinical trial dealing with a new vaccine for Measles and myeloma. Multiple myeloma is a cancer of plasma cells in the bone marrow, which also causes skeletal or soft tissue tumors. This cancer usually responds to immune system-stimulating drugs, but eventually overcomes them and is rarely cured (1).
     Two people were given a single dose of MV-NIS, an engineered measles virus that is selectively toxic to myeloma plasma cells (bone marrow). Both patients responded, showing reduction of both bone marrow cancer and myeloma protein. One of the patients, a 49-year-old woman, the one who experienced the symptoms above, experienced complete remission of myeloma and has been clear of the disease for over six months. The other patient, who did not respond as well still saw improvement and evidence that the intravenously administered virus specifically targeted the sites of tumor growth (3).

Figure 1. (2) A, Serial single-photon emission computed tomography (SPECT)–computed tomography (CT) images from patient 1 at baseline (d-1) and on days 8 (d8) and 15 (d15) after MV-NIS infusion at the level of the left frontal plasmacytoma. B, Serial SPECT-CT images from patient 2 at baseline and on days 8, 15, and 28 (d28) after MV-NIS infusion at the level of the inguinal region. C, Anteroposterior fluorodeoxyglucose positron emission tomography (PET)–CT image obtained before MV-NIS administration and the corresponding iodine 123 SPECT-CT images obtained 8 days and 28 days after virus administration.

     As you can see, there is a large reduction in the size of this woman's tumor. As promising as this news is however, there was a distinct difference between the two patients. The woman who saw complete remission, her tumors were mostly found in her bone marrow while the other patient's tumors were mostly found in her leg muscles. Stephen Russel, the head researcher, stated that the trial taught the researchers two things:, “No. 1, you need a really big dose and No. 2, the patient needs to not have an antibody to the virus.” (1) This may prove challenging to upcoming phases and since there was such a small sample size of two patients it may be difficult to be entirely positive that this works for a large population, or they just got lucky. However, any remission is good news so there is a lot of hope for the future. It will be interesting to follow this vaccine through the rest of the phases.

1. Bever, Lindsey. "Woman’s Cancer Killed by Measles Virus in Unprecedented Trial." Washington Post. The Washington Post, 14 May 2014. Web. 16 May 2014.
2. Russell, Stephen J., MD, PhD, Mark J. Federspiel, PhD, Kah-Whye Peng, PhD, Caili Tong, MS, David Dingli, MD, PhD, William G. Morice, MD, PhD, Val Lowe, MD, Michael K. O'Connor, PhD, Robert A. Kyle, MD, Nelson Leung, MD, Francis K. Buadi, MD, S. Vincent Rajkumar, MD, Morie A. Gertz, MD, Martha Q. Lacy, MD, and Angela Dispenzieri, MD. "Remission of Disseminated Cancer After Systemic Oncolytic Virotherapy." Mayo Clinic Proceedings (2014). Web. 16 May 2014.
3. Nellis, Bob. "Mayo Clinic First to Show Virotherapy Is Promising Against Multiple Myeloma." Mayo Clinic News Network. Mayo Clinic, 16 May 2014. Web. 16 May 2014.