RCTs are not required
Private plaintiffs cannot pursue lack of substantiation claim


On April 18 2017 Judge Vasquez granted summary judgment to Bayer in a consumer class action over its probiotic dietary supplement Phillips' Colon Health in In re Bayer Phillips' Colon Health Probiotics Sales Practices Litigation.(1) This important decision should help to rein in the onslaught of lawsuits that improperly target dietary supplements.

First, the court's decision reinforces that dietary supplements are not regulated as drugs and structure/function claims need not be supported by randomised controlled clinical trials (RCTs).

Second, the opinion makes clear that private consumer class actions cannot be premised on a 'lack of substantiation' theory.

RCTs are not required

Recognising the many health benefits of dietary supplements, Congress enacted the Dietary Supplement Health and Education Act 1994 to ensure that supplements can be marketed and sold without following the stringent requirements imposed on prescription drugs. In April 2001 the Federal Trade Commission (FTC) promulgated guidance, stating that the relevant standard for dietary supplements is "competent and reliable scientific evidence".

The FTC guidance makes clear that drug-level randomised clinical trials are not required. Instead, "competent and reliable scientific evidence" is a "flexible" standard and "[t]here is no fixed formula for the number or type of studies required". Even:

"[r]esults obtained in animal and in vitro studies will… be examined, particularly where they are widely considered to be acceptable substitutes for human research or where human research is infeasible."

In addition, "[e]pidemiologic evidence may be an acceptable substitute for clinical data" in some circumstances.

However, in conflict with its own published guidance, the FTC and class action lawyers have brought a number of suits against dietary supplement companies on the grounds that the supplement claims are not supported by RCTs. Courts have rejected these attempts to ignore federal law. The most recent defeat for the FTC came in US v Bayer where the court denied the FTC's attempt to demand drug-level clinical trials to support proper structure function claims for the same probiotic product – Phillips' Colon Health.(2)

Unfortunately, despite this defeat, the FTC continues to demand RCTs for dietary supplements. Following that decision, an FTC attorney reportedly stated: "I don't think [the US v. Bayer decision] was about whether you need clinical trials."(3) The most recent judicial decision makes clear that this statement is incorrect.

The court in In re Bayer Phillips' Colon Health reinforced that clinical trials are not required. The court relied heavily on US v Bayer and explained that the FTC opinion held that "RCTs are not required to meet the standard of 'competent and reliable scientific evidence'" and that "dietary supplements do not" need to meet the "higher standard" that applies to drugs.(4) In summary, the US v Bayer opinion means what it says: dietary supplements must be regulated as Congress intended – they are supplements and not drugs.

Private plaintiffs cannot pursue lack of substantiation claim

The court also closed the door to a claim favoured by private plaintiffs – a 'lack of substantiation' claim. Plaintiffs often sue manufacturers under state consumer fraud laws arguing that a particular food or supplement claim is not adequately substantiated by scientific evidence, where they cannot prove that the claim is scientifically false.

In In re Bayer Phillips' Colon Health the court held that "[m]erely proving that the claims are unsubstantiated is insufficient".(5) Rather, "a plaintiff must put forth affirmative evidence of falsity".(6) The plaintiffs' expert in this case testified that his only basis for saying that Bayer's claims were false was that Bayer had no supportive RCT and that a number of existing RCTs did not show positive results. The court rejected this testimony and explained that it "is nothing more than a lack-of-substantiation theory".(7) The court further described the expert's opinion as "pure speculation" or an "educated guess", both of which are wholly insufficient to survive summary judgment.

Plaintiffs around the country are pursuing similar claims based on a lack of substantiation theory and are tendering experts that apply the drug-level standard. Following the Phillips' Colon Health decision, courts should similarly reject these claims.

For further information on this topic please contact Scott Bass or Diane C McEnroe at Sidley Austin LLP's New York office by telephone (+1 212 839 5300) or email ([email protected] or [email protected]). Alternatively, contact Eugene Schoon or Kara L McCall at Sidley Austin LLP's Chicago office by telephone (+1 312 853 7000) or email ([email protected] or [email protected]). The Sidley Austin LLP website can be accessed at


(1) In re Bayer Phillips' Colon Health Probiotics Sales Practices Litigation, 11-03017 (D NJ).

(2) US v Bayer, 07-0001 (DNJ).

(3) "FTC Attorney Hoists RCT Standard For Supplement Claims, Industry Swings Back" Malcolm Spicer, Elsevier Business Intelligence, July 6 2016.

(4) Ibid, at 15.

(5) Ibid, at 20.

(6) Ibid, at 19.

(7) Ibid, at 24.

Associate Benjamin M Mundel assisted in the preparation of this update.