Modern targeted drug plus old malaria pill serve a 1-2 punch in advanced cancer patients

Apr 05, 2011

Researchers at the University of Pennsylvania School of Medicine may have found a way to turn an adaptive cellular response into a liability for cancer cells. When normal cells are starved for food, they chew up existing proteins and membranes to stay alive. Cancer cells have corrupted that process, called autophagy, using it to survive when they run out of nutrients and to evade death after damage from chemotherapy and other sources. When the Penn investigators treated a group of patients with several different types of advanced cancers with temsirolimus, a molecularly targeted cancer drug that blocks nutrient uptake, plus hydroxychloroquine, an anti-malarial drug that inhibits autophagy, they saw that tumors stopped growing in two-thirds of the patients.

Amaravadi's team will present the data at the American Association for 102nd Annual Meeting 2011 in Orlando on Tuesday, April 5.

"The results are very encouraging -- striking, even" says senior author Ravi Amaravadi, MD, an assistant professor of Medicine at Penn's Abramson Cancer Center. "Temsirolimus by itself has little effect in this patient population. Tumors laugh at it, with response percentages of just zero to 5 percent. But by combining it with hydroxychloroquine, we found that 14 out of 21 patients had stable disease after treatment, including five out of six melanoma patients."

In addition to melanoma, patients involved in the study also had colorectal, head and neck, breast, gastro-esophageal, prostate, pancreatic, lung and adrenal cancers. Not only did patients show substantial rates of disease stabilization with the treatment combination, but the researchers report that side effects observed were relatively limited; most commonly mouth sores, weight loss, nausea, and fatigue. Two patients developed infections when the large tumors they had at the start of the trial caved in on themselves as treatment killed off the internal , but both patients responded to antibiotics and were able to remain on the study regimen.

Amaravadi's group was able to see evidence of autophagy inhibition in peripheral blood cells in patients treated with the combination. And the inhibition increased with increasing doses of hydroxychloroquine, suggesting that the drug is working as they hypothesized it would.

More serious side effects, including low blood cell counts, in a previous phase I trial that combined hydroxychloroquine with chemotherapy and radiation. "That was unexpected and shows that hydroxychloroquine is an experimental drug, even though it has been approved for other treatments for many years," he says. "We didn't see that problem in this trial, so our findings show that what you combine it with is critical –– and some combinations will be less tolerable."

The researchers note that the relatively limited side effect profile of the novel temsirolimus-hydroxychloroquine combination suggests researchers may be able to layer other therapies on top of it, making the combination an even more powerful treatment.

Given the large proportion of patients who benefited from this combination in the initial cohort of patients, the investigators are currently enrolling an additional 12 patients in an expansion cohort at the 1200 mg dose of hydroxychloroquine. They are also hopeful that the drug combination will also be useful in patients with head and neck and breast cancers.

Explore further: Team identifies source of most cases of invasive bladder cancer

add to favorites email to friend print save as pdf

Related Stories

New approach to leukemia chemotherapy -- is a cure in sight?

Mar 31, 2011

Speaking at the UK National Stem Cell Network conference in York later today (31 March), Professor Tessa Holyoake from the University of Glasgow will discuss a brand new approach to treating chronic myeloid leukaemia (CML) ...

Recommended for you

Cancer stem cells linked to drug resistance

17 hours ago

Most drugs used to treat lung, breast and pancreatic cancers also promote drug-resistance and ultimately spur tumor growth. Researchers at the University of California, San Diego School of Medicine have discovered ...

Unraveling the 'black ribbon' around lung cancer

Apr 17, 2014

It's not uncommon these days to find a colored ribbon representing a disease. A pink ribbon is well known to signify breast cancer. But what color ribbon does one think of with lung cancer?

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

winthrom
not rated yet Apr 05, 2011
Advanced cancer patients are under a death watch, so this seems to be worth more attention than the small "enrolling an additional 12 patients in an expansion cohort at the 1200 mg dose of hydroxychloroquine" test group.

More news stories

Cancer stem cells linked to drug resistance

Most drugs used to treat lung, breast and pancreatic cancers also promote drug-resistance and ultimately spur tumor growth. Researchers at the University of California, San Diego School of Medicine have discovered ...

Finnish inventor rethinks design of the axe

(Phys.org) —Finnish inventor Heikki Kärnä is the man behind the Vipukirves Leveraxe, which is a precision tool for splitting firewood. He designed the tool to make the job easier and more efficient, with ...

Making graphene in your kitchen

Graphene has been touted as a wonder material—the world's thinnest substance, but super-strong. Now scientists say it is so easy to make you could produce some in your kitchen.