This is a multicenter, open label, dose escalation & expansion phase I study to evaluate the clinical safety, tolerability, PK, and preliminary efficacy of CS3006.

Inclusion Criteria:

1. Subjects with histologically or cytologically confirmed advanced or metastatic solid tumor(s) for which no effective standard therapy is available or tolerable.
2. ECOG performance status of 0 or 1.
3. Life expectancy ≥12 weeks.
4. Able to swallow and retain oral medication.
5. Subjects must have adequate organ function.
6. Use of effective contraception.

Exclusion Criteria:

1. Subjects receiving anti-cancer therapy at the time of enrollment.
2. Subjects who had prior chemotherapy, targeted therapy, immunotherapy or any other systemic anti-cancer treatment, within 14 days prior to the first dose of CS3006 or who has not recovered from adverse events due to a prior therapy.
3. Receipt of any prior therapy with a MEK inhibitor.
4. Use of any investigational anti-cancer drug within 28 days before the first dose of CS3006.
5. Current use of a prohibited medication or use during treatment of CS3006.
6. Current use of warfarin.
7. Any condition that will interfere significantly with the absorption, distribution, metabolism, or excretion of drugs.
8. History of retinal vein occlusion (RVO) or central serous retinopathy (CSR).
9. Visible retinal pathology as assessed by ophthalmologic exam.
10. Intraocular pressure > 21mm Hg as measured by tomography.
11. Glaucoma diagnosed within one month prior to the first dose of CS3006.
12. Known brain metastasis or other CNS metastasis that is either symptomatic or untreated.
13. Primary malignancy of CNS.
14. Evidence of severe or uncontrolled systemic diseases.
15. Subjects with clinically significant cardiovascular disease.
16. QTc interval >= 450 msecs for male or >= 470 msecs for female
17. Known history of HIV.
18. Subjects with active Hepatitis B or C infection
19. History of immediate or delayed hypersensitivity reaction or idiosyncrasy to drugs chemically related to CS3006.

For more information regarding trial participation, please contact at cstonera@cstonepharma.com