AbbVie has been making waves with the U.S. Food and Drug Administration due to deaths linked back to its North Chicago manufacturing facility.

The federal agency believes the drugmaker has done a sub-par job at investigating those complaints. This raises eyebrows at a company which has already set itself on the radar for a controversial increase in drug prices.

Humira is used to treat a variety of symptoms resulting from rheumatoid arthritis, psoriatic arthritis, Crohn’s disease, ulcerative colitis and severe chronic plaque psoriasis. Humira is used in children four years and older to treat polyarticular juvenile idiopathic arthritis as well.

Humira produced over 65 percent of AbbVie’s sales last year, resulting in over $18 billion worldwide. The drug company not only inflated the price of its medication, but has been directly linked to five deaths in the United States.

The FDA was concerned that AbbVie did not take any initiative to look into five deaths that were tied to lots from a manufacturing facility in North Chicago. Both Humira and Rituxan (a medication used in various lymphoma patients) were the culprits.

Upon further investigation, the FDA found that there were another 8 to 11 complaints that had been unaccounted for. The agency indicated the way AbbVie dealt with the death threats was “inadequate.”

The FDA noted other inadequacies such as AbbVie’s lack of evaluating reserve samples for evidence of deterioration.

Furthermore, AbbVie has made controversy due to Humira’s major price increase over the last few years. According to the International Federation of Health Plans, Humira is available in countries outside the United States for a fraction of the price.

The reason it costs upwards of $38,000 a year? In a 2016 study, the Journal of the American Medical Association indicated that, “..prescription drugs are priced in the United States primarily on the basis of what the market will bear.”

Unfortunately, similar drugs on the market don’t work as effectively as Humira, which can be frustrating for both doctors and patients.