Human clinical testing shall be taken into account under this paragraph (c)(1) only to the extent that the testing relates to the use of a drug for the rare disease or condition for which the drug was designated under section 526 of the Federal Food, Drug, and Cosmetic Act. For purposes of paragraph (c)(1)(i) of this section the testing under section 505(i) exemption procedures (21 CFR part 312) of a biological product (other than a radioactive biological product intended for human use) pursuant to 21 CFR § 601.21 is deemed to be carried out under an exemption under section 505(i) of the Federal Food, Drug, and Cosmetic Act.
Determinations under paragraph (d)(1)(i)(B) of this section with respect to any drug shall be made on the basis of the facts and circumstances as of the date such drug is designated under section 526 of the Federal Food, Drug, and Cosmetic Act. Examples of diseases or conditions which in 1987 afflicted 200,000 or fewer persons in the United States are Duchenne dystrophy, one of the muscular dystrophies; Huntington's disease, a hereditary chorea; myoclonus; Tourette's syndrome; and amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease).
The term "tax imposed by chapter 1" as used in this paragraph (d)(2)(iii) does not include any tax treated as not imposed by chapter 1 of the Internal Revenue Code under the last sentence of section 53(a).
The amount paid or incurred to another member of the group for the lease of personal property owned by a member of the group is not taken into account for purposes of section 28.
26 C.F.R. §1.28-1