Promising Nanomedicine Advances to Phase II Clinical Trials
Docetaxel has long been used to treat advanced forms of prostate cancer; now an ingenious targeted drug platform will deliver this chemotherapeutic directly to tumors, allowing higher dosing with fewer side effects.
October 26, 2013 - Docetaxel is a tried and true FDA-approved chemotherapy drug (trade name Taxotere) that has been used since 2004 to treat men with advanced prostate cancer. The drug is given by IV-infusion. Docetaxel is a front-line chemotherapy treatment for men with metastatic treatment-resistant prostate cancer. Because docetaxel is given systemically (throughout the body) the drug floods the body and affects cells and tissues that are not cancerous, causing unpleasant side effects for some patients. In addition, flooding the body with the drug means only a fraction of drug is delivered where it is actually needed—to tumor cells.
With significant funding from the David H. Koch – Prostate Cancer Foundation Program in Nanotherapeutics, a highly innovative way to deliver docetaxel directly to cancer cells has been developed—a polymeric nanoparticle that delivers docetaxel directly to cancer cells. This targeted drug platform allows higher doses to be administered and reach the tumor with fewer side effects experienced by patients. This nanoparticle platform is known as Medicinal Nanoengineering and is being developed by BIND Therapeutics based in Cambridge Mass. Their nanoparticles are referred to as Accurins. Their lead drug candidate is BIND-014 which is now in Phase II clinical trials in men with metastatic treatment-resistant prostate cancer and non-small cell lung cancer.
BIND-014 has shown the ability to shrink tumor size in heavily pre-treated patients (those who have failed to adequately respond to other anti-cancer treatments) as well as in patients with tumors that were thought to be insensitive to taxane-based chemotherapies such as docetaxel. To date, BIND-014 has been well-tolerated by patients who have received the drug in Phase I clinical studies, with the most notable side effect being transient low white blood cell counts in some patients. There has been no nanoparticle-related toxicity noted in any of the study participants.
Phase I Clinical Trials BIND-014
Results of Phase I clinical trials were published last year in Science Translational Medicine. That Phase I study established tolerability of BIND-014 as well as the maximum tolerated dose safe for humans. Updated results of the Phase I study were presented at this year's AACR meeting in Washington, DC by Dr. Daniel Von Hoff. While Phase I studies are generally small and are not designed to fully measure anti-tumor responses, it is encouraging that nine out of 28 patients responded positively to BIND-014. (The study represented a variety of cancer types—a typical Phase I study design.)
Today at the 20th Annual PCF Scientific Retreat, Dr. Christopher Sweeney, Clinical Director, The Lank Center for Genitourinary Oncology, Dana-Farber Cancer Institute, presented the currently available data on BIND-014. Dr. Sweeney was one of the team members and an author detailing the study results published in Science Translational Medicine. He is a consultant for BIND, a publically traded company. Sweeney told of an 80-year-old patient in the Phase I study with advance prostate cancer who, after treatment with BIND-014, experienced a 73% decrease in serum PSA. Sweeney mentioned that the Prostate Cancer Foundation was an early supporter of the basic research behind BIND-014 that helped usher this drug candidate into clinical trials.
BIND-014 is targeted to an antigen (PSMA) found on the surface of prostate cancer cells and blood vessels in tumors that feed cancer cells.
Think of this nanoparticle technology as a Chemotherapy ExpressLine Bus Service that only makes stops at tumor sites where it delivers its therapeutic payload—docetaxel. This limits service only to tumor sites and bypasses healthy tissue along the route, sparing that healthy tissue from damage.
This summer, BIND Therapeutics announced it had begun to give BIND-014 to the first patient in a Phase II clinical trial that will assess the safety and efficacy of this drug in men with metastatic treatment-resistant prostate cancer who have not previously received chemotherapy. The trial will be a 40-patient multi-center study. From more information on this trial go to www.clinicaltrials.gov and enter NCT01812746.
Primary Outcome Measures of this Phase II study of BIND-014:
• To determine the efficacy of BIND-014 as measured by radiographic progression-free survival (rPFS) in patients with chemotherapy-naïve metastatic CRPC [ Time Frame: Patients will be followed for the duration of treatment, an expected average of 24 weeks ]
• Number of patients with a progression-free survival of 6 months.
The idea to develop aptamer-targeted nanoparticles was first conceived in 2002 and forwarded by the David H. Koch Institute for Integrative Cancer Research at MIT, Brigham and Women’s Hospital, the Dana-Farber Cancer Institute, Harvard Medical School and Weill Cornell Medical College. Funding for the research and development program was provided by both public and private sources including the MIT Institute for Integrative Center for Cancer Research, the National Institute for Biomedical Imaging and Bioengineering, a prostate cancer SPORE Grant awarded to Dana-Farber Cancer Institute, the National Cancer Institute, the NCI Alliance in Nanotechnology and the Prostate Cancer Foundation.
The PCF has heavily funded early work on the development of BIND-014 as well as research on PSMA.
Dr. Sweeney is the principal investigator on the ICECaP Initiative. The Intermediate Clinical Endpoints in Cancer of the Prostate (ICECaP) Working Group is a multidisciplinary team of academic cancer researchers with an interest in prostate cancer and advocates who are joining forces to improve the efficiency of adjuvant clinical trials for prostate cancer in an effort to move potentially life-saving treatments into standard practice sooner.