Inclusion Criteria:

          -  Participants who have provided voluntary written consent for participation in this
             clinical study

          -  Participants to whom the rules for complying with this clinical study have been
             adequately explained, and who intend to and can comply with those rules

          -  Participants age ≥ 20 years at the time of informed consent

          -  Participants with a histological and/or cytological diagnosis of solid tumor who
             failed standard therapies, or for which no appropriate treatment is available

          -  Participants with adequate function of major organs

          -  Participants with Performance Status score of 0 to 1 established by the Eastern
             Cooperative Oncology Group

          -  Participants who are expected to survive for 3 months or longer after starting
             administration of the investigational drug

          -  Washout period required from the end of prior treatment to the first administration of
             study drug

          -  Participants agree to submit blood samples prior and during study treatment for
             progressive disease markers.

          -  (Part 1 only in some of additional participants to explore candidate optimal biologic
             dose) Participants agree to be hospitalized between Cycle 1 Day 1 (C1D1) and C1D8 at
             least so that plasma, urine, and feces samples for pharmacokinetic analysis could be
             submitted.

        Inclusion Criteria (Part 2 only):

        - Measurable disease meeting the criteria.

        Inclusion Criteria (Part 2: Her2-negative breast cancer cohort only):

          -  Histologically or cytologically confirmed adenocarcinoma of Her2-negative breast
             cancer

          -  Female participants who had received at least an anthracycline and/or taxane treatment
             for the neoadjuvant/adjuvant or chemotherapy for refractory or relapse breast cancer
             and progressed radiographically

        Inclusion Criteria (Part 2: Other solid tumors cohort only):

          -  Any refractory or relapse solid tumor types as follows:

               1. Histologically or cytologically confirmed diagnosis of squamous cell carcinoma of
                  head and neck (oropharynx, hypopharynx, larynx)

               2. Histologically or cytologically confirmed diagnosis of other tumor (e.g., gastric
                  or gastro-esophageal adenocarcinoma, and colon/rectum adenocarcinoma)

                  Exclusion Criteria:

          -  Medical history of clinically significant cardiovascular impairment

          -  Concomitant systemic infection requiring medical treatment (including bacterial
             infection and fungal infection)

          -  Participants who test positive for human immunodeficiency virus (HIV antibody)

          -  Active viral hepatitis (B or C) (*) as demonstrated by positive serology or requiring
             treatment (*)hepatitis B surface antigen (HBsAg), hepatitis B surface antibody
             (anti-HBs)/hepatitis B core antibody (HBcAb) and anti-hepatitis C virus (HCV) antibody
             test.

          -  Effusion requiring drainage

          -  Participants whose toxicity of previous treatment has not recovered to Grade 1 or
             lower (except for alopecia)

          -  Other active malignancy

          -  Females who are breastfeeding or pregnant at Screening or Baseline (as documented by a
             positive beta-human chorionic gonadotropin [ß-hCG] or human chorionic gonadotropin
             [hCG]).

          -  Women of childbearing potential or men of impregnate potential who don't agree that
             both the participant and his/her partner will use a medically effective method for
             contraception during the study and after study drug discontinuation (male; 90 days,
             female; 60 days)

          -  Known intolerance to the study drug or any of the excipients

          -  Any medical or other condition that in the opinion of the investigator(s) would
             preclude the participant's participation in the study

          -  Scheduled for surgery during the study

          -  Diagnosed with meningeal carcinomatosis

          -  Participants with brain or subdural metastases are not eligible.

        Exclusion Criteria (Part 2 only):

        - Previous treatment with halicondrin B or -like compound.