99-1938. Laxative Drug Products for Over-the-Counter Human Use  

  • [Federal Register Volume 64, Number 19 (Friday, January 29, 1999)]
    [Rules and Regulations]
    [Pages 4535-4540]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 99-1938]
    
    
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    DEPARTMENT OF HEALTH AND HUMAN SERVICES
    
    Food and Drug Administration
    
    21 CFR Part 310
    
    [Docket No. 78N-036L]
    RIN 0910-AA01
    
    
    Laxative Drug Products for Over-the-Counter Human Use
    
    AGENCY: Food and Drug Administration, HHS.
    
    ACTION: Final rule.
    
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    SUMMARY: The Food and Drug Administration (FDA) is issuing a final rule 
    establishing that the over-the-counter (OTC) stimulant laxative 
    ingredients danthron and phenolphthalein are not generally recognized 
    as safe and effective and are misbranded. FDA is issuing this final 
    rule as part of its ongoing review of OTC drug products after 
    considering data and information on the safety of danthron and 
    phenolphthalein.
    
    EFFECTIVE DATE: January 29, 1999.
    
    FOR FURTHER INFORMATION CONTACT: Cheryl A. Turner, Center for Drug 
    Evaluation and Research (HFD-560), Food and Drug Administration, 5600 
    Fishers Lane, Rockville, MD 20857, 301-827-2222.
    
    SUPPLEMENTARY INFORMATION:
    
     I. Background
    
         In the Federal Register of March 21, 1975 (40 FR 12902), FDA 
    published, under Sec. 330.10(a)(6) (21 CFR 330.10(a)(6)), an advance 
    notice of proposed rulemaking to establish a monograph for OTC 
    laxative, antidiarrheal, emetic, and antiemetic drug products, together 
    with the recommendations of the Advisory Review Panel on OTC Laxative, 
    Antidiarrheal, Emetic, and Antiemetic Drug Products (the Panel), which 
    was the advisory review panel that evaluated data on the active 
    ingredients in these classes. In the advance notice of proposed 
    rulemaking, the Panel recommended Category I (generally recognized as 
    safe and effective and not misbranded) status for the OTC stimulant 
    laxative ingredients danthron and phenolphthalein (40 FR 12902 at 12908 
    to 12910). The agency concurred with the Panel's Category I 
    classification of these ingredients in the tentative final monograph 
    published in the Federal Register of January 15, 1985 (50 FR 2124 at 
    2152 to 2156).
    
         In the Federal Register of September 2, 1997 (62 FR 46223), FDA 
    reopened
    
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    the administrative record and proposed to amend the tentative final 
    monograph for OTC laxative drug products to reclassify danthron and 
    phenolphthalein from Category I to Category II (not generally 
    recognized as safe and effective or misbranded) and to add these 
    ingredients to a list of nonmonograph active ingredients. Interested 
    persons were invited to submit comments on or before October 2, 1997. 
    Data and information received after the administrative record was 
    reopened are on display in the Dockets Management Branch (HFA-305), 
    Food and Drug Administration, 5630 Fishers Lane, rm. 1061, Rockville, 
    MD 20852.
         This final rule declares OTC laxative drug products containing the 
    active ingredients danthron or phenolphthalein to be new drugs within 
    the meaning of section 201(p) of the Federal Food, Drug, and Cosmetic 
    Act (the act) (21 U.S.C. 321(p)), for which an application or 
    abbreviated application (hereinafter called application) approved under 
    section 505 of the act (21 U.S.C. 355) and 21 CFR part 314 is required 
    for marketing. In the absence of an approved application, products 
    containing these drugs for laxative use also would be misbranded under 
    section 502 of the act (21 U.S.C. 352).
         The final rule amends part 310 (21 CFR part 310) to include the 
    laxative active ingredients danthron and phenolphthalein by adding new 
    Sec. 310.545(a)(12)(iv)(B). Because a safety problem has been 
    identified for OTC drug products containing danthron and 
    phenolphthalein, this final rule is effective on the date of its 
    publication in the Federal Register. Therefore, on or after January 29, 
    1999, no OTC drug products that are subject to this final rule may be 
    initially introduced or initially delivered for introduction into 
    interstate commerce unless they are the subject of an approved 
    application.
         Nineteen comments were received in response to the proposed rule 
    on danthron and phenolphthalein. All comments addressed 
    phenolphthalein. Copies of the comments received are on public display 
    in the Dockets Management Branch (address above).
    
     II. The Agency's Conclusions on the Comments
    
         1. Three comments agreed that phenolphthalein should be removed 
    from OTC laxative drug products because of the public health importance 
    of this matter and the need for prompt closure by FDA. Eight comments 
    contended that phenolphthalein should remain in OTC laxative drug 
    products because the National Toxicology Program (NTP) data (Ref. 1) 
    were insufficient to determine whether phenolphthalein posed a risk to 
    humans, and because phenolphthalein has been safely and effectively 
    used for many years. Several consumers indicated that they will not be 
    able to find another laxative ingredient as effective as 
    phenolphthalein, and believed that their health will be affected if 
    they can no longer use phenolphthalein.
         As stated in this document, the agency concludes that 
    phenolphthalein is not safe and not of sufficient medical value to 
    outweigh the potential risks associated with its OTC use. As there are 
    at least 25 other laxative ingredients available for OTC use, the 
    agency concludes that consumers have access to sufficient alternative 
    laxatives.
         2. Four comments offered alternatives to removing phenolphthalein 
    from OTC laxative drug products. Three comments argued that stronger 
    warning statements on the phenolphthalein product label and public 
    education would adequately alert consumers of the potential health risk 
    to humans and emphasize appropriate use of the drug.
         The agency concludes that stronger warning statements and public 
    education will not change the potential risk of using phenolphthalein 
    and that this risk is not acceptable given the benefit for laxative use 
    in the OTC target population.
         3. Three manufacturers contended that actual carcinogenic effects 
    of phenolphthalein in humans have not been determined and recommended 
    that studies be conducted to evaluate the safe use of phenolphthalein 
    in humans. One manufacturer stated that these additional data may take 
    2 to 3 years to obtain and recommended a moratorium on the decision to 
    remove phenolphthalein from OTC laxative drug products. One 
    manufacturer offered to conduct a case control human surveillance 
    safety study. Two manufacturers recommended that FDA or another agency 
    conduct studies to evaluate the safe use of phenolphthalein in humans.
         The agency notes that it is the manufacturer's responsibility to 
    conduct studies to determine whether phenolphthalein is safe for human 
    use. Because of public health concerns, the agency disagrees that 
    phenolphthalein should remain on the market while further human safety 
    studies are being conducted and is stopping initial introduction or 
    initial delivery for introduction into interstate commerce of OTC 
    laxative drug products containing phenolphthalein as of the date this 
    final rule is published in the Federal Register.
         4. Two manufacturers submitted comments (Refs. 2 through 8) 
    questioning the validity of the NTP data (Ref. 1). They argued that: 
    (1) The studies failed to demonstrate a proposed mechanism of genotoxic 
    action for phenolphthalein that is relevant to humans, (2) alternative 
    mechanisms were not considered, (3) the data obtained from the p53 
    deficient mouse study are inconsistent with what was expected based on 
    the 2-year carcinogenicity studies, (4) the NTP data do not provide a 
    sufficient basis for FDA to draw firm conclusions regarding the 
    potential human carcinogenicity of phenolphthalein, and (5) there are 
    no relevant human data to draw any firm conclusions regarding potential 
    risk of phenolphthalein in humans.
         One comment submitted four consultant reports (Refs. 2 through 5), 
    which reanalyzed the NTP data. One report by Roe (Ref. 3) directed 
    criticisms primarily at the p53 deficient mouse study and the ``null'' 
    mouse, which lacks both wild type p53 alleles. Roe dismissed the 
    positive genotoxicity results as apparent only under conditions of 
    toxicity or in some cases as an estrogenic effect. Roe also rejected 
    the findings of genotoxicity demonstrated for phenolphthalein in the 
    Chinese Hamster Ovary (CHO) cell chromosome aberrations assays, in the 
    several positive in vivo micronucleus assays, and in the mutation and 
    chromosomal aberration findings in the Syrian hamster embryo cells 
    (SHE) transformation assay by Tsutsui et al. (Ref. 9).
         Two reports from CanTox U.S., Inc., (Refs. 2 and 4) concurred with 
    the estrogenic mechanism of carcinogenesis proposed by Roe. CanTox 
    proposed that an aneugenic effect may be involved and questioned the 
    validity of the mutagenicity data presented by Tsutsui et al. (Ref. 9) 
    for the SHE cell assay, noting that the control data were not different 
    from the treated groups.
         One comment included a position paper on phenolphthalein from the 
    European Agency for the Evaluation of Medicinal Products, Committee for 
    Proprietary Medicinal Products (CPMP) (Ref. 7). The CPMP argued that 
    while carcinogenicity and genotoxicity for phenolphthalein were 
    confirmed by data from a transgenic mouse model, the systemic exposures 
    to active drug, both in the conventional rodent bioassays and p53 
    mouse, appeared to be well in excess of those likely to be encountered 
    in normal human use. CPMP stated that the extent of risk to humans 
    cannot be established without adequate mechanistic data addressing 
    whether a threshold exists for the carcinogenic
    
    [[Page 4537]]
    
    effects in mice and the in vivo genotoxic effects. CPMP added that it 
    was unable to verify from original data FDA's statement that the 
    ``systemic exposures in rodents were approximately fortyfold to 
    seventyfold and sixtyfold to hundredfold the human exposure for rats 
    and mice, respectively.''
         Another comment (Ref. 8) also reanalyzed the NTP data and 
    concluded that phenolphthalein was a genotoxic carcinogen in rodents. 
    No new information was submitted.
         The comments did not submit any new data, but focused on 
    interpreting findings that already were available. The issue of 
    carcinogenicity through a genotoxic mechanism was discussed in the 
    proposed rule (62 FR 46223 at 46224) and at the April 30, 1997, FDA 
    Center for Drug Evaluation and Research (CDER) Carcinogenicity 
    Assessment Committee (CAC) meeting (Ref. 10). The CAC concluded that 
    the study in p53 heterozygous mice supports other evidence that 
    phenolphthalein may be carcinogenic through a genotoxic mechanism. 
    There was a clear dose-dependent increase in the incidence of thymic 
    lymphoma in the p53 assay, confirming one of the primary tumors of 
    concern to the CAC based on its original evaluation of the 2-year assay 
    data. These tumors occurred at doses that showed no other signs of 
    toxicity. Further, the CAC believed that the results of several of the 
    assays and data support a genotoxic clastogenic mechanism. 
    Phenolphthalein was positive in chromosome aberration tests and showed 
    chromosomal abnormality and hypoxanthine phosphoribosyltransferase 
    (hprt) mutations in the SHE cell assay, where nontoxic doses caused 
    cell transformation, mutations, and chromosome aberration. The p53 
    protein accumulation in the nucleus of thymic lymphoma cells of the 
    original 2-year mouse bioassay, coupled with the deletion of the wild 
    type p53 allele in the thymic lymphomas of p53 mice, is indicative of 
    interaction with the p53 gene as a target site. In vivo, repeated 
    exposure resulted in micronuclei in both the original bioassay and in 
    p53 mice studies. In the p53 mice, an increase in peripheral blood 
    micronucleus occurred even at the low doses (about 15 times the human 
    exposure) with increased duration of treatment without establishing a 
    no effect dose. Further, the exposures used to demonstrate these in 
    vivo and in vitro genotoxic effects were in the range that could occur 
    with human laxative use.
         With regard to use of the p53 assay and its usefulness for 
    quantitative risk assessment, NTP used the p53 heterozygous mouse assay 
    to test phenolphthalein; therefore, many of the comments in Roe's 
    report regarding the ``null'' mouse (which lacks both wild type p53 
    alleles) do not apply. Information is available regarding the 
    responsiveness of the p53 model and the types of compounds to which it 
    responds. To date, when using a 6-month protocol design, the p53 mouse 
    only appears to respond to compounds known to be carcinogenic and 
    genotoxic, and not to compounds that are carcinogenic and nongenotoxic. 
    There is also no evidence to date that the p53 heterozygous mouse assay 
    that was used responds to carcinogens at significantly lower doses than 
    are positive in standard bioassays. Data for the micronucleus response 
    from Tice et al. (Ref. 11) indicate that, while the maximal response in 
    the p53 mouse is greater than for other strains of mice, response below 
    2,000 milligram/kilogram/day is similar to that of normal CD-1 mice 
    similarly treated with phenolphthalein. Furthermore, the tumor response 
    to phenolphthalein in the p53 model occurred over a dose range that 
    could have been predicted based on the results of the 2-year bioassay 
    in mice (assuming a genotoxic mechanism). Thus, the agency considers it 
    reasonable to use the p53 model as a part of the weight of evidence in 
    assessing a drug suspected of being a genotoxic carcinogen.
         The agency further notes that the CAC's evaluation was not a 
    quantitative assessment for either the standard bioassays or the p53 
    assay, rather the data were viewed qualitatively considering exposure. 
    The evidence from several experimental studies indicating that 
    phenolphthalein acts through a genotoxic mechanism via deoxyribonucleic 
    acid (DNA) structural damage decreases the utility of a direct 
    quantitative risk assessment. The genotoxicity data were also 
    considered in the evaluation of the 2-year bioassay results, which 
    contributed significantly to the conclusion of a relevant risk to 
    humans. The p53 mouse assay was conducted under test conditions where 
    factors such as target organ toxicity did not confound its 
    interpretation, and where exposures and pharmacodynamic effects were 
    well characterized. Thus, the results of the p53 mouse assay appear to 
    be more likely relevant to humans than the results from the 2-year 
    bioassay as conducted.
         Further, the agency disagrees with Roe's dismissal of the 
    genotoxic findings in the CHO cell chromosome aberration, micronucleus, 
    and SHE cell transformation assays as apparent under conditions of 
    toxicity or in some cases as an estrogenic effect. The agency is aware 
    that phenolphthalein is known to have estrogenic activity. The 
    information available on phenolphthalein indicates that its potency for 
    binding at estrogen receptors and for induction of estrogenic effects 
    is low compared to endogenous estrogens (by about a factor of 
    103 and 104 less than estradiol). Given the 
    concentrations of phenolphthalein achieved in the bioassays, this 
    action may be considered to have little overall contribution to the 
    estrogenic load in the rodent models tested. The types of tumors 
    observed for phenolphthalein are generally unlike those observed with 
    other estrogenic chemicals. While there may be some contribution by 
    estrogenic effects in the tumor response, the estrogenic effects appear 
    most relevant for the ovarian tumors observed only in the 2-year mouse 
    bioassay.
         The genotoxic effects of phenolphthalein were observed under 
    conditions compatible with the International Conference on 
    Harmonization (ICH) guidance for the conduct of such genotoxicity 
    studies. Although the repeat dose micronucleus assay that was 
    originally reported was conducted at doses causing bone marrow 
    toxicity, which could be viewed as confounding the results, the 
    micronucleus assay conducted in the p53 mouse exhibited little evidence 
    of toxicity and yielded results essentially identical to those of the 
    prior assays. Thus, excessive toxicity is not essential to the 
    micronucleus response for phenolphthalein. Further, this assay, 
    although not part of the standard ICH test battery, is believed by many 
    in the scientific community to be a more comprehensive assessment than 
    the acute dose micronucleus assay, as it allows for any metabolic 
    induction processes that might occur in vivo. This assay also allows 
    exposures to achieve steady state conditions and reduces the 
    uncertainty of appropriate sampling times, which can confound the 
    standard acute assessments. Use of such tests is in accordance with ICH 
    recommended guidelines for additional genotoxicity testing where 
    positive findings have been observed in carcinogenicity studies.
         The agency notes that there was an error in the Tsutui et al. 
    report (Ref. 9), in that the number of mutations found in the control 
    group for the SHE cell transformation assay should have been reported 
    as <0.25 x="">-6. The Tsutui et al. findings for the control 
    treatment are consistent with historical experience and less than 1/16 
    the response in phenolphthalein treated cells. The positive control 
    produced an effect only
    
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    threefold greater than phenolphthalein. Thus, these data indicate a 
    mutational effect for phenolphthalein.
         The data also indicate that both aneuploidy and structural damage 
    are caused by phenolphthalein. Tice et al. (Ref. 11) showed a possible 
    increase in aneuploidy based on the kinetochore analysis. There was 
    also significant evidence of structural damage; phenolphthalein 
    treatment caused an approximate fourfold increase in micronuclei with 
    structural damage and an eightfold increase in aneugenic damage 
    calculated based on the ratio of normochromatic erythrocytes and 
    polychromatic erythrocytes, and the increase in micronuclei. Also, an 
    effect on aneuploidy was not observed in the study by Tsutsui et al. 
    (Ref. 9) with SHE cells, whereas DNA structural damage and mutation 
    were reported. The view that aneuploidy is the primary mechanism of 
    genetic damage related to the carcinogenic effect also ignores the 
    evidence of structural damage observed in the CHO cell chromosomal 
    aberration studies, including those done by NTP, with responses 
    approaching those seen with the positive control. Although the loss of 
    heterozygosity observed in tumors from the p53 mouse could be explained 
    by an aneugenic mechanism, it could also be the result of a chromosome 
    break or deletion of a significant segment of the p53 region targeted 
    by the assay. This allele loss was also specific for the p53 wild-type 
    gene, with no effect on the null allele. Such a selective effect would 
    not be anticipated from chromosome loss by an aneugenic mechanism 
    functioning at the spindle apparatus.
         One CanTox report (Ref. 5) presented information on the effects of 
    phenolphthalein on thymidylate synthase (TS) activity and the potential 
    relationship to the genotoxic and carcinogenic effects observed 
    following phenolphthalein treatment in various systems. This report was 
    evaluated by FDA's Executive CAC and Genetic Toxicology Committees (the 
    Committees) (Ref. 12), which noted that the TS enzyme inhibitory 
    activity was reported for a bacterial source and could differ between 
    the bacterial and human or other mammalian forms, but there is no 
    information available for assessing increased or decreased sensitivity. 
    The Committees found no available information for estimation of 
    intracellular versus extracellular concentrations of phenolphthalein to 
    determine whether the in vivo phenolphthalein concentrations are within 
    a reasonable range of those that were studied in vitro for TS 
    inhibition. The inhibitor effects, however, appear to occur at plasma 
    concentrations of phenolphthalein tenfold to hundredfold greater than 
    the plasma concentrations associated with in vivo effects. There was 
    also no information available on the TS activity of the glucuronide or 
    other metabolites of phenolphthalein. In addition, the nucleotide pool 
    disruption model lacked in vivo data and other information showing that 
    a disruption of nucleotide pools was caused by phenolphthalein or that 
    nucleotide pool effects were involved in the observed responses to 
    phenolphthalein. The Committees noted that the effects of 
    phenolphthalein on induction of micronuclei could be considered 
    consistent with an effect on TS, based on comparisons of effects with 
    5-fluorouracil (5-FU) and methotrexate (MTX) treatment. However, the TS 
    inhibitory activity does not appear consistent with or explain the 
    other observed effects of phenolphthalein. In contrast to the assays 
    conducted on phenolphthalein, 5-FU and MTX failed to increase SHE cell 
    transformation. This suggests that, if phenolphthalein is active as a 
    TS inhibitor at the tested concentrations, its effects on SHE cells 
    (such as transformation, mutation, and chromosomal aberration) appear 
    independent of the TS activity. Also, phenolphthalein is associated 
    with increased chromosomal aberrations in CHO cells only in the 
    presence of metabolic activation. This contrasts with the ability of 
    phenolphthalein to directly inhibit TS. The comment's suggestion that 
    the effect in CHO cells is due to fragile site damage in the CHO cell 
    genome is not consistent with data provided by Witt et al. (Ref. 6), 
    nor with the observations on CHO cells discussed at the April 2, 1996, 
    CAC meeting (Ref. 13). In both data sets, there were increases in both 
    complex and simple chromosomal breaks. In the latter data set, the 
    proportionate response of simple and complex breaks appears similar to 
    that caused by cyclophosphamide (a known genotoxicant used as the 
    positive control for the assay). There was no discussion by the comment 
    as to why a fragile site response would not be relevant for human 
    adverse effects. The Committees noted that in a chromosomal aberration 
    assay on human peripheral blood lymphocytes tested in vitro (Ref. 14), 
    there was evidence of a clastogenic response from one of two subjects 
    tested. While there is evidence that phenolphthalein can inhibit TS in 
    some in vitro systems, the Committees stated that the data do not 
    support the argument that TS inhibition explains all of the genetic 
    damage observed in tests conducted on phenolphthalein, and that TS 
    inhibition is the underlying mechanism of tumor formation in the three 
    in vivo assays conducted. The Committees concluded that the data on TS 
    inhibition do not refute the potential relevance of phenolphthalein's 
    toxicologic effects for humans.
         The CPMP (Ref. 7) contended that the extent of risk in humans 
    cannot be established because the mechanistic data are inadequate and 
    the phenolphthalein doses used in the study were excessive. The agency 
    is not aware of any available data that would suggest that the 
    mechanisms thought to account for tumor induction by phenolphthalein in 
    experimental animals would not also operate in humans. Further, the 
    phenolphthalein exposures used to demonstrate the in vivo and vitro 
    genotoxic effects were in the range of those that humans use to cause 
    laxation. The agency also notes that the exposure information for 
    phenolphthalein that the CPMP could not verify was based on data 
    obtained from a kinetic study (Ref. 15) sponsored by the 1992-1993 
    Nonprescription Drug Manufacturers Association Phenolphthalein Study 
    Group.
         After review of all the available data, the agency concludes that 
    phenolphthalein caused chromosome aberrations, cell transformation, and 
    mutagenicity in mammalian cells. Because benign and malignant tumor 
    formation occurs at multiple tissue sites in multiple species of 
    experimental animals, phenolphthalein is reasonably anticipated to have 
    human carcinogenic potential.
    
    III. References
    
         1. Comment No. RPT7, Docket No. 78N-036L, Dockets Management 
    Branch.
         2. CanTox U.S., Inc., ``Discussion of New Data Related to 
    Phenolphthalein Presented at the April 30, 1997 Meeting of the 
    Carcinogenicity Assessment Committee of the U.S. Food and Drug 
    Administration,'' June 9, 1997, in Comment No. C167, Docket No. 78N-
    036L, Dockets Management Branch.
         3. Roe, F. J., ``Opinion on the Safety of Phenolphthalein as an 
    Ingredient of OTC Laxative Preparations,'' August 28, 1996, in 
    Comment No. C180, Docket No. 78N-036L, Dockets Management Branch.
         4. CanTox U.S., Inc., ``Evaluation of the Rodent 
    Carcinogenicity of Phenolphthalein,'' October 1, 1997, in Comment 
    No. C180, Docket No. 78N-036L, Dockets Management Branch.
         5. CanTox U.S., Inc., ``The Relevance of the Role of 
    Phenolphthalein as an Inhibitor of Thymidylate Synthase for the 
    Interpretation of the Genotoxic Potential and Carcinogenicity 
    Assessment of this Compound,'' December 4, 1997, in Comment No. 
    C186, Docket No. 78N-036L, Dockets Management Branch.
    
    [[Page 4539]]
    
         6. Witt, K. L. et al., ``Phenolphthalein: Induction of 
    Micronucleated Erythrocytes in Mice,'' Mutation Research, 341:151-
    160, 1995, in Comment No. C186, Docket No. 78N-036L, Dockets 
    Management Branch.
         7. Comment No. C189, Docket No. 78N-036L, Dockets Management 
    Branch.
         8. Comment No. RPT9, Docket No. 78N-036L, Dockets Management 
    Branch.
         9. Tsutsui, T. et al., ``Cell Transforming Activity and 
    Genotoxicity of Phenolphthalein in Cultured Syrian Hamster Embryo 
    Cells,'' unpublished manuscript, 1997, in Comment No. RPT7, Docket 
    No. 78N-036L, Dockets Management Branch.
         10. Comment No. MM13, Docket No. 78N-036L, Dockets Management 
    Branch.
         11. Tice, R. R. et al., ``Tumorigenicity Studies of Dietary 
    Phenolphthalein (CAS No. 77-09-8) in TSG-p53 Transgenic Female 
    Mice,'' final report, April 11, 1997, in Comment No. RPT7, Docket 
    No. 78N-036L, Dockets Management Branch.
         12. Comment No. MM15, Docket No. 78N-036L, Dockets Management 
    Branch.
         13. Comment No. MM12, Docket No. 78N-036L, Dockets Management 
    Branch.
         14. Comment No. RPT10, Docket No. 78N-036L, Dockets Management 
    Branch.
         15. BTC Study No. P0392002 in Comment No. RPT11, Docket No. 
    78N-036L, Dockets Management Branch.
         5. One comment expressed concern about the availability of an 
    acceptable bowel cleansing system for use by physicians if the use of 
    phenolphthalein is banned. The comment argued that its bowel cleansing 
    system containing phenolphthalein, magnesium citrate, and bisacodyl 
    should not be considered an OTC laxative. The comment stated that if 
    phenolphthalein cannot be used, patients may be misdiagnosed because 
    adequate bowel cleansing was not achieved prior to undergoing a bowel 
    examination. The comment requested that the agency allow the continued 
    sale of phenolphthalein in bowel cleansing systems if the product is 
    adequately labeled, limited to a one-time application, and purchased 
    and used under a physician's supervision.
         This final rule prohibits the use of phenolphthalein in OTC 
    laxative drug products. If an OTC bowel cleansing system is 
    reformulated to contain a different laxative ingredient, data must be 
    submitted to the rulemaking for OTC laxative ingredients to support the 
    safety and effectiveness of the reformulated bowel cleansing system. 
    Bowel cleansing systems that contain phenolphthalein and are limited to 
    purchase and use under a physician's supervision may be submitted for 
    agency review in a new drug application.
         6. One comment stated that if phenolphthalein is reclassified as a 
    Category II ingredient in the final rule, an immediate effective date 
    would be unfair because it would cause significant economic harm to 
    manufacturers of phenolphthalein. The comment recommended that a 1-year 
    transition period be allowed for manufacturers to reformulate their 
    laxative products, which will involve the purchase and production of 
    new materials and, possibly, new equipment. The comment did not present 
    any information that was not previously addressed in the proposed rule.
         Because over 1 year has passed since the proposal was published, 
    providing adequate time for reformulation, the agency denies the 
    comment's request. In the preamble to the proposed rule (58 FR at 46226 
    to 46227), FDA found good cause under 5 U.S.C. 553(d) and 21 CFR 
    10.40(c)(4) for an immediate effective date for this final rule. In the 
    reasons given in that preamble, as well as the fact that an additional 
    period of more than 1 year has passed; the agency confirms the finding 
    of good cause for an immediate effective date for this final rule.
    
     IV. The Agency's Final Conclusions on Danthron and Phenolphthalein
    
         Based on new data and information, the agency is reclassifying the 
    stimulant laxative ingredients danthron and phenolphthalein from 
    Category I (monograph) to Category II (nonmonograph) and is adding 
    danthron and phenolphthalein to the list of stimulant laxatives in 
    Sec. 310.545(a)(12)(iv). The current list in that section is 
    redesignated as Sec. 310.545(a)(12)(iv)(A) and danthron and 
    phenolphthalein are being included in new Sec. 310.545(a)(12)(iv)(B). 
    As a result of this reclassification of danthron and phenolphthalein, 
    the amendments proposed in Secs. 334.18, 334.30, 334.32, 334.60, and 
    344.66 (62 FR 46223 at 46227) will be finalized in the final rule for 
    OTC laxative drug products, to be published in a future issue of the 
    Federal Register.
    
     V. Analysis of Impacts
    
         One comment was received in response to the agency's request in 
    the proposal for specific comment on the economic impact of this 
    rulemaking (62 FR 46223 at 46225). (See comment 6 of this document.)
         FDA has examined the impacts of this final rule under Executive 
    Order 12866 and the Regulatory Flexibility Act (5 U.S.C. 601-612). 
    Executive Order 12866 directs agencies to assess all costs and benefits 
    of available regulatory alternatives and, when regulation is necessary, 
    to select regulatory approaches that maximize net benefits (including 
    potential economic, environmental, public health and safety, and other 
    advantages; distributive impacts; and equity). Under the Regulatory 
    Flexibility Act, if a rule has a significant economic impact on a 
    substantial number of small entities, an agency must analyze regulatory 
    options that would minimize any significant impact of the rule on small 
    entities.
         Title II of the Unfunded Mandates Reform Act (2 U.S.C. 1501 et 
    seq.) requires that agencies prepare a written statement and economic 
    analysis before proposing any rule that may result in an expenditure in 
    any 1 year by State, local, and tribal governments, in the aggregate, 
    or by the private sector, of $100 million (adjusted annually for 
    inflation).
         The agency believes that this final rule is consistent with the 
    principles set out in the Executive Order and in these two statutes. 
    The purpose of this final rule is to establish conditions under which 
    the OTC stimulant laxative ingredients danthron and phenolphthalein are 
    not generally recognized as safe and effective. Cessation of marketing 
    of OTC laxative drug products containing danthron occurred in 1987. 
    Therefore, no reformulation or relabeling will be necessary for this 
    ingredient.
         Products containing phenolphthalein will need to be reformulated 
    to replace the ingredient with another laxative active ingredient. A 
    number of laxative ingredients in proposed part 334 (50 FR 2124 at 
    2152) could be used. In addition, most OTC laxative drug products 
    containing phenolphthalein have already been reformulated since the 
    proposal was published.
         When the proposed rule was published, the agency was aware of only 
    one phenolphthalein dosage form, a flavored chewable tablet. Sales of 
    this dosage form by all manufacturers were about $20 million in 1995 
    (most attributed to one large manufacturer), comprising about 3 percent 
    of the total retail market for laxative products. The major 
    manufacturer of this product informed the agency on August 29, 1997 ( 
    Ref. 1), that it planned to reformulate the product with another OTC 
    laxative ingredient within 60 days.
         Because these products must be manufactured in compliance with the 
    pharmaceutical current good manufacturing practices (21 CFR parts 210 
    and 211), all firms have the necessary skills and personnel to perform 
    the tasks of reformulation, validation, and relabeling either in-house 
    or by contractual arrangement. The rule will not require any new 
    reporting and recordkeeping activities. No additional professional 
    skills are needed. There are no other Federal rules
    
    [[Page 4540]]
    
    that duplicate, overlap, or conflict with this rule.
         Based on the agency's understanding that most manufacturers have 
    already reformulated or otherwise are in the process of reformulating, 
    the agency expects that this final rule will not be economically 
    significant under Executive Order 12866, nor would it impose an 
    Unfunded Mandate (as that term is described in the Unfunded Mandate 
    Reform Act). The agency also believes that it has undertaken steps to 
    reduce the burden to small entities. Nevertheless, some entities may 
    incur significant impacts, especially manufacturers that still must 
    reformulate their phenolphthalein products and, to a lesser extent, 
    private label manufacturers that provide labeling for a number of the 
    affected products. Danthron was removed from OTC laxative drug products 
    in 1987 and has not been available for approximately 10 years. 
    Therefore, it is unlikely that reclassification of danthron as a 
    nonmonograph ingredient would have any economic impact. This economic 
    analysis, together with other relevant sections of this document, 
    serves as the agency's final regulatory flexibility analysis, as 
    required under the Regulatory Flexibility Act.
    
     VI. Reference
    
        1. Comment No. C173, Docket No. 78N-036L, Dockets Management 
    Branch.
    
     VII. Paperwork Reduction Act of 1995
    
         This final rule contains no collections of information. Therefore, 
    clearance by the Office of Management and Budget under the Paperwork 
    Reduction Act of 1995 is not required.
    
     VIII. Environmental Impact
    
         The agency has determined under 21 CFR 25.31(c) that this action 
    is of a type that does not individually or cumulatively have a 
    significant effect on the human environment. Therefore, neither an 
    environmental assessment nor an environmental impact statement is 
    required.
    
     List of Subjects in 21 CFR Part 310
    
         Administrative practice and procedure, Drugs, Labeling, Medical 
    devices, Reporting and recordkeeping requirements.
         Therefore, under the Federal Food, Drug, and Cosmetic Act and 
    under authority delegated to the Commissioner of Food and Drugs, 21 CFR 
    part 310 is amended as follows:
    
     PART 310--NEW DRUGS
    
         1. The authority citation for 21 CFR part 310 continues to read as 
    follows:
    
        Authority: 21 U.S.C. 321, 331, 351, 352, 353, 355, 360b-360f, 
    360j, 361(a), 371, 374, 375, 379e; 42 U.S.C. 216, 241, 242(a), 262, 
    263b-263n.
    
         2. Section 310.545 is amended by redesignating paragraph 
    (a)(12)(iv) as paragraph (a)(12)(iv)(A) and by revising the newly 
    redesignated heading, by adding paragraphs (a)(12)(iv)(B) and (d)(29), 
    and by revising paragraph (d) introductory text and paragraph (d)(1) to 
    read as follows:
    
    
    Sec. 310.545   Drug products containing certain active ingredients 
    offered over-the-counter (OTC) for certain uses.
    
         (a) * * *
         (12) * * *
         (iv)(A) Stimulant laxatives--Approved as of May 7, 1991. * *  *
         (iv)(B) Stimulant laxatives--Approved as of January 29, 1999.
    Danthron
    Phenolphthalein
    * * * * *
         (d) Any OTC drug product that is not in compliance with this 
    section is subject to regulatory action if initially introduced or 
    initially delivered for introduction into interstate commerce after the 
    dates specified in paragraphs (d)(1) through (d)(29) of this section.
         (1) May 7, 1991, for products subject to paragraphs (a)(1) through 
    (a)(2)(i), (a)(3) through (a)(4), (a)(6)(i)(A), (a)(6)(ii)(A), (a)(7) 
    (except as covered by paragraph (d)(3) of this section), (a)(8)(i), 
    (a)(10)(i) through (a)(10)(iii), (a)(12)(i) through (a)(12)(iv)(A), 
    (a)(14) through (a)(15)(i), and (a)(16) through (a)(18) of this 
    section.
    * * * * *
         (29) January 29, 1999, for products subject to paragraph 
    (a)(12)(iv)(B) of this section.
    
        Dated: January 20, 1999.
     William K. Hubbard,
     Associate Commissioner for Policy Coordination.
    [FR Doc. 99-1938 Filed 1-28-99; 8:45 am]
    BILLING CODE 4160-01-F
    
    
    

Document Information

Effective Date:
1/29/1999
Published:
01/29/1999
Department:
Food and Drug Administration
Entry Type:
Rule
Action:
Final rule.
Document Number:
99-1938
Dates:
January 29, 1999.
Pages:
4535-4540 (6 pages)
Docket Numbers:
Docket No. 78N-036L
RINs:
0910-AA01: Over-the-Counter (OTC) Drug Review
RIN Links:
https://www.federalregister.gov/regulations/0910-AA01/over-the-counter-otc-drug-review
PDF File:
99-1938.pdf
CFR: (3)
21 CFR 310.545(a)(12)(iv)
21 CFR 310.545(a)(12)(iv)(B)
21 CFR 310.545