RUTGERS (US) — Delivering chemotherapy through inhalation significantly improves the rate of successfully treating cancer tumors in the lungs, new animal studies show.
Lung cancer kills about 1.5 million men and women around the world—more than the number of people who die from breast, colon, pancreatic, and prostate cancers combined.
Researchers say this happens, in part, because many patients with lung cancer are not diagnosed until they are in the advanced or metastatic stage of the disease and treatment options are limited mainly to surgery and conventional intravenous chemotherapy.
The new research indicates that inhalation therapy reduces systemic damage done to healthy lung cells and other organs while improving the treatment of lung tumors.
“The development of additional more effective and safe approaches to treatment of this disease is vitally important,” says Tamara Minko, professor and chair of the department of pharmaceutics at Rutgers.
“Up until now, limited clinical efficiency and significant toxicity have represented two critical barriers restricting progress in the therapy of advanced lung cancer.”
With conventional chemotherapy treatment for lung cancer, the drugs tend to accumulate in the liver, kidney, and spleen—with less making it to the lungs. But in the new study, 83 percent of the drugs delivered via inhalation therapy, as compared to 23 percent with the intravenous injection, were delivered directly to the lungs and predominantly accumulated in tumor cells.
Researchers were able to enhance the efficacy of lung cancer treatment by using a combination of tiny nanoparticles of existing cancer drugs—smaller than a speck of dust—and small interfering molecules that shut down the ability of the cancer cells to resist attack.
In the most recent four-month animal study, published in the Journal of Controlled Release, the lung tumors of mice treated with inhalation therapy virtually disappeared.
The next step, says Minko, will be to conduct clinical trials to determine whether the same positive effects would occur in humans. Currently, those being treated for lung cancer must deal with severe toxic side effects of conventional chemotherapy.
Developed nanoparticle-based lung cancer inhalation therapy would enable those being treated to use the same type of inhaler prescribed to people with asthma, she says.
“The proposed novel treatment much more effectively killed resistant cancer cells when compared with conventional anti-cancer drugs and showed superior efficiency over the traditional chemotherapy.”
Researchers from Oregon State University contributed to the study.