A Study to Evaluate the Safety, Tolerability, and Activity of KD025 in Subjects With Chronic Graft Versus Host Disease

Approximately 48 subjects will be enrolled to receive orally administered KD025 200 mg QD
(once daily), KD025 200 mg BID (twice daily), or KD025 400 mg QD. Once a recommended dose is
chosen, approximately 40 additional subjects will be enrolled into the study at that dose.

Study drug will be administered in 28-day cycles until disease progression or unacceptable
toxicity. Subjects may receive study drug in the inpatient or outpatient setting.

Inclusion Criteria:

- Adult male and female subjects at least 18 years of age who have had allogenic bone
marrow transplant (BMT) or hematopoietic stem cell transplantation (HSCT).

- Receiving glucocorticoid therapy and calcineurin therapy or glucocorticoid therapy
alone for cGVHD at study entry. Subjects on calcineurin therapy only, without
glucocorticoid therapy, are not eligible. Subjects also receiving other therapies
thought not to be immunosuppressive (such as extracorporeal photopheresis; ECP), will
be considered for enrollment in this study on a case-by-case basis.

- Have persistent active cGVHD manifestations, as defined by 2014 NIH Consensus
Development Project on Criteria for Clinical trials in cGVHD, after at least 2 months
of steroid therapy.

- No more than 3 prior lines of treatment for cGVHD.

- Karnofsky Performance Scale of > 40.

- Adequate organ and bone marrow functions evaluated during the 14 days prior to
enrollment as follows:

- Absolute neutrophil count ≥ 1.5 × 109/L (without myeloid growth factors within 1
week of study entry)

- Platelet count ≥ 50 × 109/L (without transfusion or thrombopoietin or
thrombopoietin analogues within 2 weeks of study entry)

- Adequate safety laboratory values:

- Total bilirubin ≤ 1.5 × upper limit of normal (ULN)

- ALT and AST ≤ 3 × ULN

- Glomerular filtration rate (GFR) ≥ 30 mL/min/1.73 m2 using the MDRD-4 variable
formula

- Female subjects of childbearing potential have a negative pregnancy test at screening.
Females of childbearing potential are defined as sexually mature women without prior
hysterectomy or who have had any evidence of menses in the past 12 months. However,
women who have been amenorrheic for 12 or more months are still considered to be of
childbearing potential if the amenorrhea is possibly due to prior chemotherapy, anti
estrogens, or ovarian suppression.

- Women of childbearing potential (i.e., menstruating women) must have a negative urine
pregnancy test (positive urine tests are to be confirmed by serum test) documented
within the 24-hour period prior to the first dose of study drug.

- Sexually active women of childbearing potential enrolled in the study must agree to
use two forms of accepted methods of contraception during the course of the study and
for 3 months after their last dose of study drug. Effective birth control includes:

- IUD plus one barrier method;

- Stable doses of hormonal contraception for at least 3 months (e.g., oral,
injectable, implant, transdermal) plus one barrier method;

- 2 barrier methods. Effective barrier methods are male or female condoms,
diaphragms, and spermicides (creams or gels that contain a chemical to kill
sperm); or

- A vasectomized partner

- For male patients who are sexually active and who are partners of premenopausal women:
agreement to use two forms of contraception as in criterion 10 above during the
treatment period and for at least 3 months after the last dose of study drug.

- Able to provide written informed consent prior to the performance of any
study-specific procedures.

Exclusion Criteria:

- Female subject who is pregnant or breastfeeding.

- Receiving an investigational GVHD treatment within 28 days of study entry.

- Has acute GVHD.

- Taking any medication known to be a moderate or strong inhibitor of the CYP3A4 isozyme
or any drugs that are moderate or strong CYP3A4 inducers.

- History or other evidence of severe illness or any other conditions that would make
the subject, in the opinion of the investigator, unsuitable for the study (such as
poorly controlled psychiatric disease or coronary artery disease).

- Regular and excessive use of alcohol within the 6 months prior to study entry defined
as alcohol intake > 14 drinks per week in a man or > 7 drinks per week in a woman.
Approximately 10 g of alcohol equals one "drink" unit. One unit equals 1 ounce of
distilled spirits, one 12-ounce beer, or one 4-ounce glass of wine.

- Known history of human immunodeficiency virus (HIV) or active hepatitis C virus (HCV)
or hepatitis B virus (HBV).

- Diagnosed with another malignancy (other than malignancy for which transplant was
performed) within 3 years of enrollment, with the exception of completely resected
basal cell or squamous cell carcinoma of the skin, resected in situ cervical
malignancy, resected breast ductal carcinoma in situ, or low-risk prostate cancer
after curative resection.

- Relapse of the underlying cancer or post-transplant lymphoproliferative disease at the
time of screening.

- Has had previous exposure to KD025 or known allergy/sensitivity to KD025 or any other
ROCK-2 inhibitor.

- Taking other immunosuppressant drugs for GVHD, including mTor inhibitors (Note: Only
steroids, calcineurin inhibitors, and ECP are acceptable).

- QTcF > 450 msec.