The World of Pain journalism collaboration brought together reporters in more than 10 countries to investigate pharmaceutical companies’ role in the global opioids crisis. The latest installment of the series focused on how German drugmaker Grünenthal has promoted painkillers tramadol and tapentadol using misleading tactics.

Here’s four key tactics reporters found Grünenthal used across borders – and the company’s response. 

Sponsoring studies

Medical journals are an important arena for pharmaceutical companies, as this is where their drugs’ benefits and side effects are described to professionals. Shaping the discourse over products here influences how doctors view and prescribe them.

The Examination looked into Grünenthal’s promotion of its latest opioid, tapentadol, a strong opioid used for moderate and severe pain. 

The company has funded studies and articles in peer-reviewed journals saying tapentadol causes less dependence and is less likely to be abused than other opioids on the market. Articles and studies with the same conclusion have been written by companies that Grünenthal licenses and by Grünenthal-funded researchers.

In one such article, published in 2014 in the peer-reviewed journal CNS Drugs, Grünenthal employees claimed that “the reduced dependence seen with tapentadol” might be because it acts on two separate bodily systems that affect pain.  Since then more articles repeat this assertion. The Examination also spoke with multiple former Grünenthal employees who repeated this claim. One said Grünenthal relied on studies as well as written materials and seminars when teaching sales representatives to promote the drug this way. 

But is the claim on dependency true? The Examination sent it to six independent experts who reviewed the research and said there is no convincing evidence to support it. 

Funding pain associations and patient groups

Another common tactic used by pharmaceutical companies is to fund medical organizations and patient groups, which can promote drugs to fellow prescribers or to patients who can lobby their doctor for it. These groups can also pressure regulators and policymakers, who may not realize that the organization receives industry funding.

Grünenthal has paid millions of dollars to help support patient groups and medical organizations, some of which have lobbied to expand tapentadol’s availability.

A data analysis by The Examination found Grünenthal has paid more than $9 million to help support at least 900 European patient groups and medical organizations in the last decade. 

In Latin America, the company has funded pain associations in Brazil, Mexico, Peru, Argentina and Colombia as part of its expansion tactics in the region, according to reporting by World of Pain media partners in the region, the Latin American Center for Investigative Journalism (CLIP), Salud Con Lupa, El Elspectador and PlatôBR. One company-funded pain association lobbied the Mexican Congress to loosen regulations around prescribing tapentadol. 

The head of another Peruvian pain association, which also received funding from Grünenthal, promoted tapentadol as  “less addictive than traditional opioids” to a room full of doctors at a pain conference in Lima last year, according to Salud Con Lupa. He heralded the drug as a means to generate profits for doctors.

Funding doctors

Doctors are highly trusted members of communities and their behavior influences their peers as well as their patients. Decades of evidence shows that drug companies funding doctors for research, speaking engagements or for consultation increases prescribing.

Grünenthal provided funding to scores of doctors and researchers through its Change Pain campaign. It set up advisory panels filled with doctors and scientists across Europe and Latin America. They met regularly and produced opinion pieces and articles about pain treatment, which sometimes refer to opioids sold by Grünenthal. 

One 2016 paper by Change Pain Latin America published in an academic journal criticized “regulatory barriers that restrict access, distribution, and appropriate prescribing of opioids in the region” and encouraged doctors not to let the fear of addiction stop them using these drugs to treat pain patients, according to CLIP.

The company also set up a website for doctors in Latin America called Medical Beyond, which featured videos intended to teach medics about pain management. One video featured Silvia Allende Pérez, head of a public pain clinic in Mexico and former Grünenthal employee, promoting tapentadol and its “advantages over other opioids,” and included a Grünenthal-branded slide claiming tapentadol has a “minimum potential of abuse” despite it having a high abuse potential. 

The slide also downplays the drug’s risk of  respiratory depression – or slower breathing – despite this condition being a well-known side effect of opioids and is listed as such by Mexican health officials. Grünenthal took down the website, saying the company would review all content, after The Examination’s inquiries.

In Brazil, two pain specialists and an orthopaedic surgeon that receive speaking fees from  Grünenthal wrote a paper promoting tapentadol for the treatment of osteoarthritis, according to PlatôBR. Guidelines in the U.K. do not recommend opioids for this condition. Grünenthal also funded doctors to hold evening classes teaching other medics on how to treat chronic pain, PlatôBR found. 

Fighting regulation

Tapentadol's predecessor, a blockbuster drug called tramadol, was developed by Grünenthal in the 1970s and is now abused widely around the world. PlatôBR found that between 2020 and 2024, tramadol became the Brazilian Ministry of Health’s most purchased medicine for the treatment of pain in the public health system.

For years, Grünenthal fought against stronger regulations or controls on this drug, according to German investigative news outlets Paper Trail Media and the news magazine Der SPIEGEL. Reporters revealed how German authorities were also complicit in the failure to regulate tramadol to prevent addiction.

Tramadol is the only opioid in Germany that is entirely exempt from the strict regulations for controlled substances. The country’s Ministry of Health decided not to put stricter controls on the drug in 2011 after a recommendation from a committee convened by the Federal Institute for Drugs and Medical Devices. It is now the most widely prescribed opioid in the country.

The German reporters revealed that multiple experts with ties to Grünenthal sat on the committee making the recommendation. One was a former Grünenthal manager, another was an anesthesiologist who had co-authored several studies on tramadol with Grünenthal and another was a professor whose university role was sponsored by a Grünenthal foundation.

The impact on German society was huge. Reporters interviewed pain patients that became addicted to tramadol, mothers who had lost children to tramadol addiction and young people who abused tramadol before moving on to other illicit substances. Independent experts said it was a mistake not to put stricter controls on the drug. 

The Federal Institute for Drugs and Medical Devices told Paper Trail Media that all the information available at the time was taken into account. Grünenthal said that tramadol’s abuse potential was based on scientific data that was presented transparently to the authorities.

Grünenthal’s response

In a statement sent to the World of Pain reporting collaboration, Grünenthal acknowledged that “a few” company documents had mischaracterized tapentadol’s addiction risks.

The company commissioned an independent audit in 2019 and found that claims that tapentadol was less addictive than other opioids were “not backed up by sufficient scientific references.”

But Grünenthal denied actively promoting the drug as less addictive and said addiction risks are included in every pack of pills and in product information for doctors.

And, it said, tapentadol is approved for moderate to severe chronic pain in some countries and the labels vary depending on local regulations.

Regarding funding of doctors, pain associations and patient groups Grünenthal said it operates with “the highest ethical standards” when partnering.  The company ensures that payments are only made for clearly defined services provided and that there are no expectations regarding  prescribing behavior or other considerations on the part of our partners, the statement said. “Specifically, Grünenthal does not lobby or influence clinical guidelines or treatment decisions,” a spokesperson wrote.  

Grünenthal also said that the currently available data “suggest an overall lower level of abuse of tramadol in comparison with  other opioids in most regions of the world” and that the company appropriately characterizes the risk-benefit profile of the drug, which has been available from other manufacturers in its generic form since the late 1990s.