Inclusion Criteria:

          -  Willing and able to give written informed consent.

          -  Age ≥ 18 years.

          -  Have cytologically or histologically confirmed advanced or metastatic melanoma and
             having received no prior systemic therapy for metastatic disease.

          -  Have at least 1 site of disease measurable by RECIST 1.1 that has not been treated
             with local therapy within 6 months of study treatment. Tumor lesions situated in a
             previously irradiated area are considered measurable if progression has been
             demonstrated in such lesions.

          -  Have at least 1 site of disease accessible to repeat biopsies for tumor sequencing and
             immunological analysis. This site may be a target lesion as long as it will not become
             unmeasurable by the biopsy procedure.

          -  Have Eastern Cooperative Oncology Group Performance Status (ECOG PS) of 0 or 1 with an
             anticipated life expectancy of > 6 months.

          -  Recovered from all toxicities associated with prior treatment to acceptable baseline
             status (for laboratory toxicities, see below limits for inclusion) or a National
             Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) version
             4.03, Grade of 0 or 1, except for toxicities not considered a safety risk (e.g.,
             alopecia or vitiligo).

          -  Screening laboratory values must meet the following criteria and should be obtained
             within 30 days (or 45 days if a biopsy is repeated) prior to study treatment:

               1. White blood cell (WBC) count ≥ 3 × 103/µL

               2. Platelet count ≥ 100 × 103/µL

               3. Hemoglobin > 9 g/dL

               4. Serum creatinine ≤ 1.5 × upper limit of normal (ULN)

               5. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 × ULN
                  or ≤ 5 × ULN for patients with liver metastases

               6. Total bilirubin ≤ 1.5 × ULN (except in patients with Gilbert Syndrome who can
                  have total bilirubin < 3.0 mg/dL).

          -  Female patients of childbearing potential must have a negative serum or urine
             pregnancy test within 7 days prior to receiving the first dose of study medication. If
             the urine test is positive or cannot be confirmed as negative, a serum pregnancy test
             will be required.

          -  Female patients of childbearing potential must be willing to use an adequate method of
             contraception, as outlined in the protocol, for the course of the study through 120
             days after last dose of study medication.

          -  Male patients of childbearing potential must agree to use an adequate method of
             contraception, as outlined in the protocol, starting with the first dose of study
             therapy through 120 days after the last dose of study therapy. Abstinence is
             acceptable if this is the usual lifestyle and preferred contraception for the patient.

        Exclusion Criteria

          -  Is currently participating and receiving study therapy or has participated in a study
             of an investigational agent and received study therapy or used an investigational
             device within 4 weeks of first dose of treatment.

          -  Received any systemic therapy for advanced or metastatic cancer treatment including
             immunotherapeutic agents such as anti-programmed cell death protein 1 (anti-PD-1),
             anti-PD-L1, anti-CD40, or anti-cytotoxic T-lymphocyte-associated antigen 4
             (anti-CTLA-4) antibody therapy.

          -  Have had a prior anti-cancer monoclonal antibody (mAb) within 4 weeks prior to study
             Day 1 or who has not recovered (i.e., ≤ Grade 1 or at baseline) from AE due to agents
             administered more than 4 weeks earlier.

          -  Have had prior chemotherapy, targeted small molecule therapy, or radiation therapy
             within 30 days prior to study Day 1 or who has not recovered (i.e., ≤ Grade 1 or at
             baseline) from AEs due to a previously administered agent.

               1. Note: Patients with ≤ Grade 2 neuropathy or ≤ Grade 2 alopecia are an exception
                  to this criterion and may qualify for the study.

               2. Note: If patients received major surgery, they must have recovered adequately
                  from the toxicity and/or complications from the intervention prior to starting
                  therapy.

          -  Received radiation therapy at the biopsy sites.

          -  Received prior tyrosine kinase inhibitor therapy or palliative radiation within 7 days
             of Cycle 1/Day 1.

          -  Have known active central nervous system (CNS) metastases and/or carcinomatous
             meningitis. Patients with previously treated brain metastases may participate provided
             they are stable (without evidence of progression by imaging [using the identical
             imaging modality for each assessment, either magnetic resonance imaging (MRI) or
             computed tomography (CT) scan] for at least 4 weeks prior to the first dose of trial
             treatment and any neurologic symptoms have returned to baseline), have no evidence of
             new or enlarging brain metastases, and are not using steroids for at least 7 days
             prior to trial treatment. This exception does not include carcinomatous meningitis,
             which is excluded regardless of clinical stability.

          -  Have active autoimmune disease that has required systemic treatment in the past 2
             years (i.e., with use of disease-modifying agents, corticosteroids, or
             immunosuppressive drugs). Replacement therapy (e.g., thyroxine, insulin, or
             physiologic corticosteroid replacement therapy for adrenal or pituitary insufficiency)
             is not considered a form of systemic treatment.

          -  Have a diagnosis of immunodeficiency or is receiving chronic systemic steroid therapy
             (in dosing exceeding 10 mg daily of prednisone equivalent) or any other form of
             immunosuppressive therapy within 7 days prior to the first dose of trial treatment.
             The use of physiologic doses of corticosteroids may be approved after consultation
             with the Sponsor.

          -  Received a live vaccination within 30 days of planned treatment start date.

          -  Have an active infection requiring systemic therapy.

          -  Have a history of sensitivity or allergy to mAbs or immunoglobulin G (IgG).

          -  Have a history of allogeneic bone marrow transplantation.

          -  Have a known history of Human Immunodeficiency Virus (HIV) (HIV 1/2 antibodies).

          -  Have known active Hepatitis B (e.g., hepatitis B surface antigen [HBsAg] reactive) or
             Hepatitis C (e.g., hepatitis C virus [HCV] RNA [qualitative] is detected).

          -  Have an uncontrolled intercurrent illness including, but not limited to, ongoing or
             active infection requiring treatment, symptomatic congestive heart failure, unstable
             angina pectoris, cardiac arrhythmia.

          -  Have any underlying medical condition, psychiatric condition, or social situation
             that, in the opinion of the Investigator, would compromise study administration as per
             protocol or compromise the assessment of AEs.

          -  Have a planned major surgery.

          -  Are pregnant or breastfeeding, or expecting to conceive or father children within the
             projected duration of the trial, starting with the screening visit through 120 days
             after the last dose of trial treatment.

          -  Nursing women are excluded from this study because there is an unknown but potential
             risk of AEs in nursing infants secondary to treatment of the mother with nivolumab,
             personalized neoantigen peptides, adjuvant, ipilimumab, and APX005M.

          -  Have a history of additional invasive metastatic disease (other than melanoma), except
             for the following:

               1. Individuals with a history of invasive metastatic disease are eligible if they
                  have been disease free for at least 2 years and are deemed by the Investigator to
                  be at low risk for recurrence of that metastatic disease;

               2. Individuals with basal cell carcinoma of the skin, squamous cell carcinoma of the
                  skin, in situ cervical cancer, or local papillary thyroid cancer, who have
                  undergone therapy with curative intent.

          -  Have severe hypersensitivity (≥ Grade 3) to nivolumab and/or any of its excipients.

          -  Have mucosal melanoma, uveal melanoma, or acral lentiginous melanoma.