According to a publication from the Arizona BioIndustry Association, Dr. Rachna Shroff and a team of researchers from the Arizona Cancer Center are studying the use of nab-paclitaxel (a pancreatic cancer drug) to treat certain advanced biliary tract cancers.
About Biliary Tract Cancers
Cancers affecting the biliary tract (comprised of the liver, gallbladder, and bile ducts) are relatively rare. There are some 15,000 new diagnoses every year in the United States. However, these cancers are often aggressive, and patients face poor prognoses — the five-year survival rate hovers around only 20%. In advanced cases, average survival is under a year.
For some time, these cancers have been treated with a standard therapy of chemotherapy and, when appropriate, surgery. However, as the high mortality rates suggest, new avenues of treatment are sorely needed.
Pancreatic Cancer Drug Shows Promise Upon Repositioning
When Dr. Rachna Shroff first started studying potential treatments for biliary tract cancers, it was a remarkably different time in the field. “…Little research was taking place,” Shroff recalls.
“In the decade that I’ve been treating this disease, I have seen it go from ‘zero to a hundred.'”
In 2010, a new standard of treatment was set for biliary tract cancer patients. The combination of the chemotherapy drugs gemcitabine and cisplatin has remained standard since, although providing overall survival improvement of only just over 11 months.
Dr. Shroff and other researchers at the Arizona Cancer Center are currently investigating a third drug that they believe could improve the effectiveness of the gemcitabine-cisplatin combination. Nab-paclitaxel, approved by the Food and Drug Administration in 2005, has been used for some time in the treatment of pancreatic cancer. Certain similarities between pancreatic and biliary tract cancers encouraged Dr. Shroff to study nab-paclitaxel’s potential for treating the latter.
Dr. Shroff and other researchers recruited 60 patients with advanced biliary tract cancers in a phase 2 study. At locations in Texas and Arizona, all 60 received the same combination of gemcitabine, cisplatin, and nab-paclitaxel. Results from the study were compared to the standard treatment’s historical records.
Patients in the study proved to be highly responsive to the new treatment combination. Compared to the standard treatment, survival rates were improved by 8 months (19.2 months versus 11.2). Patients were also almost 20% more likely to respond to treatment (45% response rate versus 26%).
The over a year-and-a-half survival rate was “…frankly unheard of for this disease in most patients,” according to Dr. Shroff and her colleagues.
A phase 3 study of the treatment, following-up on the success of the phase 2 study, began December 2018 and is expected to be complete by January 2024. If that trial goes well, the triple-drug combination could become the new standard treatment for newly diagnosed biliary cancer patients.
The phase 3 trial is currently still recruiting. Resources for participating can be found at ClinicalTrials.gov.
If the phase 3 trial goes well, nab-paclitaxel could be part of the standard treatment for biliary tract cancers. What do you think of the impressive phase 2 trial results? Share your thoughts with Patient Worthy!