EFFECTIVE: Biologics are a new class of drug that are genetically engineered inside living cells. The most important of them, therapeutic antibodies, can be targeted much more precisely than conventional, chemical medicines.

They are genetically engineered inside living cells and are far more precise at
treating people with conditions like rheumatism or diabetes.

A rapidly growing class of drugs is revolutionising the treatment of illnesses as varied as rheumatoid arthritis, diabetes and cancer. Known as biologics, they’re genetically engineered inside living cells. The most important of them, therapeutic antibodies, can be targeted much more precisely than conventional, chemical medicines.
On the minus side, they’re much more expensive than traditional drugs, and they have side effects.
Biologic drugs have been around for just 20 years or so and now number about 180, according to Dr Gerd Bendas from the Institute for Pharmaceutical Biology at the University of Bonn in Germany.
Before a synthetic form of insulin was developed for diabetics, the blood sugar-regulating hormone was extracted from the pancreases of animals and then purified, he says. In contrast, biologic insulin can be produced, for example, by a yeast cell into which a human gene sequence, coded for construction of the insulin protein, has been inserted.
Even more innovative than biologics that replace proteins the body naturally produces are genetically engineered therapeutic antibodies. They’re able to bind to, and thereby inhibit, specific structures in the body.
In the case of an autoimmune disorder such as rheumatism, this means – put simply – that rather than broadly disabling the immune system, they target only particular components of the system such as messenger molecules that fuel inflammation.
Depending on the type of biologic, rheumatism sufferers inject themselves with the drug at intervals of one to four weeks, says Dr Stefan Schewe, executive board member of the German Rheumatism Organization. Some biologic drugs are given by infusion every eight weeks.
Meanwhile, patients continue to take their previous medicines – traditional disease-modifying antirheumatic drugs (DMARDs). There are two reasons for this.
In the case of rheumatoid arthritis, for example, DMARDs magnify the effect of the biologic drug, explains Schewe, adding that “they also prevent the formation of antibodies against the biologic” since it’s a protein the body will normally identify as foreign and therefore defend itself against.
“If something has an effect, it can also have side effects,” Bendas says.
Among the undesirable side effects is greater susceptibility to infections. Allergic reactions or intolerances are possible as well. Nevertheless, Schewe says, “biologics have certainly brought substantial improvement in therapy for inflammatory rheumatoid diseases.”
Before taking a biologic drug, patients have to be inoculated against pneumococcal pneumonia, a type of bacterial pneumonia. And certain diseases such as tuberculosis should be ruled out before therapy starts.
Dr Gerd Glaeske, a pharmacologist and health scientist at the University of Bremen, emphasises the importance of documenting any side effects during therapy with a biologic drug. Patients should be candid about them with their doctor, he says.  
Despite the benefits of biologics, nowhere near all potential recipients are given one. They’re used for rheumatism only when DMARD therapy proves to be inadequate, Schewe says, pointing out that the high price is due to their complex manufacturing process – biologics are between 10 and 100 per cent more expensive than DMARDs – is the biggest obstacle to wider use.
Glaeske puts costs at between 50,000 and 100,000 euros (about 59,000 to 118,000 US dollars) per patient per year.
Generic biologics, also known as biosimilars, are equal to the original drugs in quality and about 20 to 30 per cent cheaper, Glaeske says. They have the same effect but may have a different structure and must go through clinical trials of their own before approval for use. Patients that don’t tolerate a biologic may have no problem with its biosimilar and vice versa.
The first biosimilar hit the market in 2006, according to Bendas. But generic biologic drugs didn’t become an economic factor until 2015, when biosimilars were developed for use against inflammatory diseases affecting many thousands of people. Bendas says about 600 new biologicals and biosimilars are in the pipeline at the moment. – DPA