Some people never learn.

A tweet from Vermont Sen. Bernie Sanders has yet again brought negative attention to Valeant Pharmaceuticals.

The drugmaker came under intense congressional scrutiny around this time last year for gouging prices on two life-saving heart drugs, Nitropress and Isuprel.

Now it has caught the ire of Sanders for jacking up the price of a lead-poison treatment it purchased in 2013. When Valeant bought the drug, a package of vials cost $950, but it now costs about $27,000, according to a report from STAT News.

Last year's heart-drug scandal and accusations of accounting malfeasance from a short seller combined to bring the once high-flying company's stock price down around 90%. It has yet to recover.

The fallout from all of that included the ouster of the company's CEO, a bunch of federal and state investigations, and a congressional hearing in which Valeant executives and board members, including billionaire hedge fund manager Bill Ackman, promised to lower prices.

According to the company's new CEO, though, they haven't.

And now Valeant's business practices are adding unnecessary pain to what can only be considered one of our country's worst man-made tragedies: the water crisis in Flint, Michigan.

More from STAT:

"'This is a drug that has long been a standard of care, and until recently it was widely accessible at an affordable price,' said Dr. Michael Kosnett, an associate clinical professor in the division of clinical pharmacology and toxicology at the University of Colorado's School of Medicine and a consultant to the California Poison Control System, who has contacted Congress. 'There's no justification for the astronomical price increases by Valeant, which limit availability of the drug to children with life-threatening lead poisoning.'"

A representative from Valeant told STAT that the increased price helps the company improve access to the drug — an excuse we've heard before from other pharmaceutical companies such as Mylan, the maker of the EpiPen.