Sexually active males must be strongly advised to use an accepted and effective method of contraceptionXx_NEWLINE_xXSexually active males and pre/perimenopausal women must agree to use an accepted and effective method of contraception or to abstain from sexual intercourse for the duration of their participation in the study and for 3 months after discontinuation of therapyXx_NEWLINE_xXWomen of childbearing potential and sexually active males must be strongly advised to practice abstinence or use an accepted and effective method of contraceptionXx_NEWLINE_xXWomen of child-bearing potential and sexually active males must agree to use at least two other accepted and effective methods of contraception and/or to abstain from sexual intercourse for the duration of their participation in the study, and for at least 4 weeks after treatment with dabrafenib or for 4 months after dabrafenib in combination with trametinib; women of child-bearing potential must use at least two other accepted and effective methods of contraception and/or to abstain from sexual intercourse for at least 5 months after the last dose of nivolumab and/or ipilimumab and sexually active males must use at least two other accepted and effective methods of contraception and/or abstain from sexual intercourse for at least 7 months after the last dose of nivolumab and/or ipilimumab; should a woman become pregnant or suspect she is pregnant while she is participating in this study, she should inform her treating physician immediatelyXx_NEWLINE_xXELIGIBILITY CRITERIA FOR RANDOMIZATION (STEP 1): Women of childbearing potential and sexually active males must be strongly advised to use an accepted and effective method of contraception or to abstain from sexual intercourse for the duration of their participation in the studyXx_NEWLINE_xXWomen of childbearing potential and sexually active males must use an accepted and effective method of contraception or to abstain from sexual intercourse for the duration of their participation in the studyXx_NEWLINE_xXWomen of childbearing potential and sexually active males must be strongly advised to use an accepted and effective method of contraception or to abstain from sexual intercourse for at least one week prior to the start of the research study, and continuing for 5 months for women of childbearing potential and 7 months for sexually active males after the last dose of the study drugsXx_NEWLINE_xXWomen of childbearing potential and sexually active males must use an accepted and effective method of contraception or to abstain from sexual intercourse for the duration of their participation in the studyXx_NEWLINE_xXWomen of childbearing potential and sexually active males must be strongly advised to use an accepted and effective method of contraception or to abstain from sexual intercourse for the duration of their participation in the studyXx_NEWLINE_xXWomen of childbearing potential and sexually active males must be strongly advised to use an accepted and effective method of contraception or to abstain from sexual intercourse for the duration of their participation in the study and until 60 days from the last study treatmentXx_NEWLINE_xXWomen of childbearing potential and sexually active males must be strongly advised to use an accepted and effective method of contraception or to abstain from sexual intercourse during the treatment period and for 31 weeks after the last nivolumab infusionXx_NEWLINE_xXWomen of childbearing potential must be strongly advised to use an accepted and effective method of contraception or to abstain from sexual intercourse for the following year until the year 1 AB-MR and DBT studies are performedXx_NEWLINE_xXWomen of childbearing potential and sexually active males must be strongly advised to use accepted and effective methods of contraception, as described in the informed consent form (ICF), or to abstain from sexual intercourse for the duration of their participation in the study; women of childbearing potential should use adequate methods to avoid pregnancy for 23 weeks after the last dose of nivolumab; sexually active males should use adequate methods to avoid pregnancy for 31 weeks after the last dose of nivolumabXx_NEWLINE_xXWomen of childbearing potential and sexually active males must be strongly advised to use an accepted and effective method of contraception or to abstain from sexual intercourse for the duration of their participation in the study and for 12 months post rituximab treatmentXx_NEWLINE_xX