Generating New Hope Through Pelotonia-Funded Research
Pelotonia funds support cancer drug development projects at Ohio State, including an early-phase clinical trial on the safety of an anticancer vaccine designed to prevent the recurrence of several types of solid tumors, a phase II clinical trial of an experimental drug for patients with certain forms of leukemia, and basic-science studies that discovered how tamoxifen-resistant breast cancer cells grow and proliferate.
The phase II clinical trial will determine the effectiveness of a promising drug called ibrutinib as a targeted agent for patients with chronic lymphocytic leukemia (CLL)/ small lymphocytic leukemia (SLL) who have not responded to or who have relapsed after standard treatment. The trial will help to identify if ibrutinib works in patients with high-risk disease as well as it works in patients with better-risk disease. It will also help to identify why some patients don’t respond for long to the drug.
Principal investigator Kami Maddocks, MD, says ibrutinib inhibits a certain protein that is believed to help blood cancer cells live and grow. “By inhibiting or ‘blocking’ the activity of this protein,” Maddocks says, “it is possible that ibrutinib may kill the cancer cells or stop them from growing”. The trial, which opened in April 2012, accrued its original target of 68 patients – many of whom have no other treatment options – and was then amended to enroll another 78 patients, which provided them access to ibrutinib during a period when the drug would not otherwise be available.
This phase II clinical trial, open only at Ohio State, is part of a larger body of research at this university and other institutions that is showing ibrutinib to have strong potential as a safe, effective, targeted treatment for patients with CLL or mantle cell lymphoma (MCL), currently incurable cancers. Studies within this body of work have already had a global impact by leading to recent FDA approval of ibrutinib for the treatment of patients with relapsed MCL. Researchers hope this agent may also soon be approved for treating CLL in certain patients.
The vaccine trial, led by overall chair Pravin Kaumaya, PhD, and clinical co-principal investigators Tanios Bekaii-Saab, MD, Jeffrey Fowler, MD, and William Carson III, MD, is in the final stages of accrual. Thirty patients have received the vaccine since the trial opened at The James in July 2011. One component of the vaccine targets a molecule that occurs at abnormally high levels in up to 30 percent of breast cancers. Another component targets a molecule that is over-expressed in many other solid tumors, including ovarian, renal, colon, lung and gastrointestinal cancers. “The goals are to determine the safety and optimal dose of the vaccine, evaluate whether it shows therapeutic benefit by stimulating the immune system to respond to the patient’s tumor, and document any clinical responses that may occur,” Kaumaya says. The investigators report that eight patients receiving the vaccine in group/dose level 1 and level 2 had stable disease, and four patients have received a six-month booster so far. One of those four also had received a 12-month booster and is to receive an 18-month booster in December. In addition, a fifth patient is due for a six-month booster.
Some 30-40 percent of breast cancer patients who are treated with tamoxifen, which works by targeting high levels of estrogen found in two thirds of cases, become resistant to this drug after about five years. A study led by Sarmila Majumder, PhD, and Bhuvana Ramaswamy, MD, showed how tamoxifen-resistant breast cancer cells grow and proliferate, and it also suggested that an experimental drug called vismodegib may offer a new targeted therapy in patients for whom tamoxifen therapy has failed. The study, published in the journal Cancer Research in 2012, showed that a signaling pathway called hedgehog takes over in promoting breast cancer growth after tamoxifen does its initial work in stopping the disease. This was later found to be true for other endocrine-resistant breast cancer, namely faslodex and aromatase inhibitor-resistant disease. But vismodegib, they learned, blocks the hedgehog pathway and inhibits the growth of tamoxifen-resistant human breast tumors in an animal model. The researchers are designing a clinical trial to use vismodegib in patients who failed endocrine therapy as a first line of treatment. “Pelotonia support has been crucial in helping us understand this potential therapy,” says Ramaswamy, who notes that Pelotonia dollars also are helping them obtain data and translate the findings for a clinical trial involving this therapy in patients with triple-negative breast cancer, which has few treatment options and poor outcomes.