An appeals court judgment last Friday means Pfizer is facing the prospect of US lawsuits from Nigerian families over a controversial clinical trial in 1996 with the company’s antibiotic Trovan (trovafloxacin).

In a split 2-1 majority ruling, the United States Court of Appeals for the Second Circuit remanded to the US District Court for the Southern District of New York two cases seeking damages under international law in connection with the Trovan trial during an epidemic of bacterial meningitis in Kano, Nigeria.

The plaintiffs allege that Pfizer flouted medical ethics in the two-week comparison of Trovan and the established antibiotic ceftriaxone, causing the deaths of 11 children and leaving many others blind, deaf, paralysed and brain-damaged.

Criminal charges and civil claims seeking more than US$2 billion in damages and restitution from Pfizer have already been filed by the state of Kano, while the federal government of Nigeria has sued Pfizer and its employees for US$7 billion in damages. Last October there were indications that Pfizer was amenable to an out-of-court settlement in these cases.

As the Court of Appeals pointed out, neither of the Nigerian actions are seeking compensation for the subjects of the tests, who are the plaintiffs in the US complaints. The Nigerian families claim that efforts by the trial participants to pursue justice in Nigeria have been thwarted by corruption in that country’s court system.

In August 2001 the first US case (Abdullahi et al) was launched against Pfizer in the District Court for the Southern District of New York under the Alien Tort Statute (ATS). This alleged that the company violated international legal norms prohibiting involuntary medical experimentation on humans by testing Trovan on Nigerian children without their consent and knowledge. A second, similar US case (Adamu et al) followed in November 2002 in the wake of a failed lawsuit against Pfizer in Kano state, Nigeria.

The two US cases were consolidated in the US District Court for the Southern District of New York, which in 2005 granted Pfizer’s motions to dismiss the actions for failure to state a claim under the ATS and on the basis of forum non conveniens (i.e., there was a more appropriate forum for the proceedings).

This decision was overturned on 30 January by two of the three judges in the United States Court of Appeals for the Second Circuit, who concluded:

- the district court incorrectly determined that the prohibition in customary international law on non-consensual human experimentation could not be enforced through the ATS;
- changed circumstances in Nigeria since the appeal was filed (i.e., the charges brought against Pfizer by the state of Kano and the Nigerian federal government) demanded a re-examination of the appropriate forum for the cases; and

- the district court incorrectly applied the US state of Connecticut’s choice of law principles in the Adamu case (which made claims under Connecticut law on the basis that the Trovan study was planned there).

Pfizer stressed that the US appeals court decision was “only a procedural ruling that may return the cases to the District Court for further consideration; it is not a determination on their merits”. Indeed, the company added, “the strong dissent by one of the judges may be grounds for further appellate proceedings”.

Pfizer “remains confident that it will prevail in these cases, and is weighing its options on how to best respond to this decision”, it stated. The company insisted the Trovan study was conducted with the approval of the Nigerian government and the consent of the participants’ parents or guardians, as well as being consistent with both international and Nigerian laws.

All the clinical evidence points to any deaths or injuries in the trial having been the direct result of the meningitis epidemic and not of the treatment provided by Pfizer, it said.