Why Life Sciences Litigation Relies on Expert Gatekeeping

Patent infringement claims in life sciences require detailed claim construction analysis to determine whether a competitor's product falls within the scope of protected intellectual property, and this construction process often determines the outcome of litigation before trial begins.

Parties dispute the meaning of technical terms in patent claims, the breadth of protection granted, and whether prior art or regulatory approval processes narrow the claims' scope. Our firm's experience with Life Sciences Intellectual Property matters shows that early claim construction briefing and expert analysis can identify dispositive defenses or infringement theories years before trial. A patent holder may assert that a generic version of a branded pharmaceutical infringes method-of-treatment claims, while the generic manufacturer argues that the claims are anticipated by prior publications or rendered obvious by the state of the art. Courts may grant summary judgment on claim construction issues if the language is unambiguous, or may schedule a Markman hearing (a claim construction proceeding) to resolve disputed terms before trial.

Product liability in life sciences requires proof that a drug or device was defectively designed, inadequately warned, or negligently manufactured, and that the defect proximately caused the plaintiff's injury, a causation standard that courts enforce rigorously through expert testimony gatekeeping.

A plaintiff alleging that a prescription medication caused serious adverse effects must present expert testimony establishing that the drug's formulation, pharmacokinetics, or known side-effect profile created a foreseeable risk of harm. Defendants often challenge the admissibility of causation opinions under standards articulated in Daubert proceedings, arguing that the expert's methodology lacks scientific reliability or that alternative causes better explain the plaintiff's injury. Regulatory approval by the FDA does not insulate a manufacturer from liability if the company withheld safety data or failed to update warnings as new information emerged, but FDA approval does create a rebuttable presumption that the product was not defectively designed under certain circumstances. Plaintiffs in mass tort litigation involving blockbuster drugs or widely used devices often face additional hurdles: proving individual causation in a population-level study, distinguishing background disease incidence from drug-induced harm, and overcoming the manufacturer's arguments about confounding factors and alternative causes.

Common regulatory violations in life sciences include failure to report adverse events within required timelines, inadequate post-market surveillance, manufacturing deviations that compromise product quality, and failure to update product warnings when new safety information becomes available.

The FDA imposes strict timelines for serious adverse event reporting, and a company's delay in notifying the agency can expose it to civil penalties, product recalls, and tort liability. Manufacturing deviations discovered during FDA inspections or internal audits may indicate systemic quality control failures, and if a defective product reaches patients, the company's knowledge of the deviation strengthens a plaintiff's claim that the harm was foreseeable and preventable. Warning label updates are particularly significant in litigation: if a company knew or should have known about a serious adverse effect but delayed updating the label, plaintiffs argue that healthcare providers and patients were deprived of critical safety information. Courts in New York and other jurisdictions may find that a company's regulatory noncompliance constitutes negligence per se, removing the need for the plaintiff to prove a standard of care through expert testimony and shifting burden-of-proof dynamics in the defendant's disfavor.

Regulatory files, including IND applications, safety reports, manufacturing records, and correspondence with regulatory agencies, provide contemporaneous evidence of what a company knew about product risks and what steps it took to address them, and this documentation often determines credibility and causation disputes at trial.

A pharmaceutical company's internal safety database showing that adverse events were reported to the company but not promptly reported to the FDA creates powerful evidence of deliberate concealment or reckless disregard. Conversely, a company's documented efforts to investigate adverse events, communicate with healthcare providers, and work with regulators on label updates may demonstrate good faith and reasonable care. Discovery disputes frequently center on the scope of regulatory files: parties fight over whether internal risk assessments, post-market surveillance studies, and regulatory correspondence are privileged, work product, or discoverable. Expert witnesses rely heavily on regulatory documentation to opine on whether a company's conduct met the standard of care and whether the company's knowledge of risks should have prompted earlier warnings or product modifications. Plaintiffs' counsel scrutinizes regulatory files for gaps, delays, or inconsistencies that suggest the company prioritized commercial interests over safety, while defense counsel highlights evidence of regulatory compliance, good-faith communication with agencies, and proactive risk management.