Drug price increases by two companies drew the attention of Congress, the press and patient advocacy groups last year, Maris wrote.
One was Valeant, whose stock price was pummeled for months after The New York Times reported that Valeant and other firms were using a network of specialty pharmacies to sustain sales of high-priced drugs and prevent patients and insurers from switching to less-expensive generic competitors.
The other was Turing Pharmaceuticals, whose then-CEO Martin Shkreli raised the price of the antiparastic medication Daraprim by more than 5,000 percent. Shkreli was indicted late last year on federal securities charges that are unrelated to the Daraprim controversy. He has pleaded not guilty to the charges.
In his report on Mylan, Maris wrote that while some of the products "may be small relative to Mylan's overall business, we do not believe that the price increases come without a real cost to patients."
"And if this turns to headline risk, the could be an impact to reputation and shareholders as well," Maris wrote in June. "In this environment, we believe 400 percent and 500 percent price increases on products are beacons for scrutiny."
Earlier this week, U.S. Sen. Amy Klobuchar, D-Minn., saying she was outraged by the price increases for EpiPen, asked the Federal Trade Commission to investigate. And her colleague, Sen. Chuck Grassley, R-Iowa, chairman of the Judiciary Committee, has written Mylan asking how it determined prices for EpiPen.
Mylan has not yet responded to a request for comment by CNBC on Tuesday.
On Monday, Mylan noted in a statement that many patients can get access to EpiPens at no cost to themselves through discount programs offered by the company.
Mylan also said that changes in the health insurance "landscape" have led to increasing numbers of people being covered by so-called high-deductible plans, which require them to pay more personally out of pocket for doctor's visits and medications.
"This current and ongoing shift has presented new challenges for consumers, and now they are bearing more of the cost," Mylan said. "This new change to the industry is not an easy challenge to address, but we recognize the need and are committed to working with customers and payors to find solutions to meet the needs of the patients and families we serve."
Doug Hirsch, co-founder and co-CEO of GoodRx, the drug price comparison site, said, "When consumers perceive that the cost of drugs is going up, often it's just their share of the costs that are going up. ... We see that all the time at GoodRx."
But he acknowledged that the price hikes are real, even in cases where an EpiPen user is not paying anything out of pocket for the devices.
"You may be paying zero, but your company may be paying $500 for that EpiPen," Hirsch said.
When asked about the array of price increases at Mylan, Hirsch said, "I'm never surprised by changes in drug pricing ... in this space, it's always more complicated and complex than you can imagine."
Hirsch said that the price hikes of EpiPen, at least in part, seem to be the result of the recall last year of Sanofi's competing product Auvi-Q, and the denial of regulatory approval for a generic competitor from Teva.
"I think we're seeing a classic scenario that we see in the drug world, which is less competition equals higher prices," he said.
Correction: Rodney Whitlock is a consultant for the Campaign for Sustainable Rx Pricing. An earlier version misstated the group's name.