Medications are often developed over many years that subsequently have unexpected effects. So with ASS and Viagra. Researchers now want to use a database to discover old, new drugs against cancer.
Drugs are developed with a very specific goal – for example, to relieve pain, lower blood pressure, and cure diseases.
The course of such a drug is rocky. It takes an average of 13 years from idea to approval. Most of the candidates don’t even make it this far.
But despite the lengthy process, there is still a surprise in the end: when drugs that were intended for a specific purpose, later or in combination with other active ingredients, show a different, unexpected effect.
Fast and cheap: Recycle medication
It is precisely this effect that researchers want to use better – to tackle nothing less than cancer. Drug repositioning is the keyword.
The advantages of this procedure: The lengthy research and approval processes have been completed and the active ingredients have been found to be safe for medical use. The further development or repositioning is faster, easier and cheaper than with a completely newly developed drug.
From old to new
Occasionally there is always positive news to report. For example, researchers at the UT Southwestern Simmons Cancer Center recently discovered a drug combination that is said to stop cancer cell growth. A drug that is already on the market is intended to counteract resistance to a promising new cancer drug – which is currently in clinical trials.
Or cancer researchers from the University of Bergen in Norway had tested hundreds of different medications over several years to find out how they affect cancer cells. They found that an antidote to parasites such as tapeworms and Giardia contains the substance NTZ (nitazoxanide), which acts as a tailor-made medicine against prostate and colon cancer.
“We discovered that this specific substance blocks the signalling pathway in the cancer cells and causes them to stop growing,” said Karl-Henning Kalland from the Department of Clinical Sciences at UiB.
It is not often that researchers discover a substance that targets certain molecules as precisely as this. A recent study confirms the results of the researchers with regard to brain tumours (glioblastoma multiforme) – but also emphasizes the need for further examinations.
Well-maintained drug library
It is often difficult to keep track of the current research situation. This is exactly where scientists from the Broad Institute at MIT and Harvard and the Dana-Farber Cancer Institute come into play. They published a study in Nature Reviews Cancer, the largest of its kind that used the drug repurposing hub.
The database currently includes over 6,000 existing drugs and compounds that are either FDA approved or have been proven safe in clinical trials. The drugs are listed with their chemical structure, effectiveness and previous uses.
With the study, the researchers also systematically examined the entire anti-cancer properties of the entire collection – which mainly consists of non-cancer drugs.
The successful search for clues
The surprise: The researchers found almost 50 active substances that could have a previously unknown cancer-fighting effect. On this basis, the development of new cancer drugs could be accelerated or existing drugs used to treat cancer could be reused.
“We thought we could count ourselves lucky if we could find a single compound with anti-cancer properties, so we were surprised to find so many,” said Todd Golub, director of the Cancer Program at the Broad Institute and colleagues.
Don’t be left to chance
“We created the drug repurposing hub to enable researchers to make these types of random discoveries more consciously,” said study lead author, Steven Corsello, an oncologist at the Dana Farber Institute and founder of the drug -Database.
One such “accidental discovery” that Corsello alludes to was, for example, acetylsalicylic acid (ASA) – better known to many as an active ingredient in the drug aspirin – was originally developed as a pain reliever. It was then further determined that the tablets can also prevent heart attacks and strokes. But does it do that? More on this in the video.
The discovery of Viagra as a sexual enhancer was also purely coincidental: Originally, the active ingredient sildenafil was to be tested against heart problems and high blood pressure, but during the study, it turned out that the active ingredient disappointed the hopes placed in it.
Nonetheless, many of the male study participants asked to be allowed to keep the preparation after the end of the research project.
The erection ability had improved drastically in all of them. By the way, Viagra is also said to provide longer breaths when mountaineering – as prophylaxis or therapy for altitude sickness.
But as amusing as this excursion into drug testing may be, there is another way.
In 2016, the news became independent that certain chemotherapy regimens work better when combined with the opioid methadone. This led to high expectations of those affected and their relatives that the agent would have an anti-tumour effect.
The German Society for Hematology and Medical Oncology (DGHO) then published an information sheet for patients, in which a clear distinction is made between the “use of methadone in pain therapy for cancer patients” and the “use as an anti-tumour drug” – cancer drug.
The German Cancer Aid also emphasized in a statement that “the use of methadone as a cancer drug outside of clinical studies is not justified”.