A Safety and Effectiveness Study of Pre-operative Artesunate in Stage II/III Colorectal Cancer

This study evaluates the safety and effectiveness of pre-operative artesunate given orally once a day for 14 days prior to surgery in patients with Stage II/III colorectal cancer.

Artesunate is an established antimalarial drug with an excellent safety profile, is well tolerated and affordable. A number of laboratory studies and one small pilot clinical study in patients with colorectal cancer have shown that artesunate can reduce the proliferation and growth of cancer cells.

Two hundred patients diagnosed with Stage II/III operable colorectal cancer will be randomly allocated to receive oral artesunate 200mg daily or a matching placebo for 14 days prior to surgery. Patients will be followed up closely for 5 years to see if giving artesunate preoperatively reduces the risk of cancer recurring after surgery.

Artesunate is an established antimalarial drug belonging to the artemisinin class of drugs, has an excellent safety profile, is well tolerated and affordable. In last two decades, artemisinins have shown potent and broad anticancer properties in a range of cell lines and animal models, supporting the hypothesis that artemisinins have the potential to be an effective anti-cancer therapy. Multiple potential mechanisms of action include anti-proliferative effects through cell-cycle disruption, reactive oxygen species (ROS) -induced DNA damage, induction of apoptosis, anti-angiogenesis, immunomodulation and induced radiosensitivity.

Despite a multi-modality treatment approach to colorectal cancer, 5 year overall survival does not currently exceed 60%. Neoadjuvant pre-operative therapy may be more effective at eradicating micrometastases compared to adjuvant therapy delivered following the delay and immunological stress of surgery. However current neoadjuvant chemotherapy regimens are often associated with significant side effects and may result in a delay in surgery whilst patients recover. A well tolerated, affordable, novel anticancer agent that could be given to patients whilst they wait for surgery, without causing a surgical delay due to treatment related toxicity, would have a significant clinical impact on patient care.

The NeoART trial is a phase II multicentre randomised, double blind, placebo controlled trial (RCT) for patients undergoing primary surgery for Stage II/III colorectal cancers. Patients are randomised (1:1 ratio) to receive either a two week course of neoadjuvant artesunate 200mg once daily or matching placebo. Both patients and health care professionals are blinded to treatment allocation arm to minimise outcome-reporting bias. The primary endpoint of the trial is recurrence free survival two years after surgery. Secondary endpoints include 2 and 5 year overall survival, treatment related toxicity, tolerability and patient quality of life. A translational sub-study looking at predictive and prognostic biomarkers is also planned.

Eligibility Criteria:
Inclusion criteria

1. Aged 18 or over
2. Histologically proven single primary site colorectal adenocarcinoma or high grade dysplasia plus unequivocal radiological evidence of invasive cancer
3. Stage II/III colorectal cancer planned for surgical resection and no clinical indication for neoadjuvant preoperative chemotherapy/chemoradiation therapy
4. WHO performance status 0,1 or 2
5. Adequate full blood count: White Cell Count (WCC) \>3.0 x 10\^9 /l; Platelets \>100 x 10\^9/l; Haemoglobin (Hb) \>80g/L
6. Adequate renal function: Glomerular Filtration Rate \>30ml/min by Cockcroft-Gault formula
7. Adequate hepatobiliary function : Bilirubin \< 3 x Upper limit normal
8. Female participants of child bearing potential must have a negative pregnancy test \< 72 hours prior to initiating study intervention and agree to avoid pregnancy using adequate, medically approved contraceptive precautions for up to 6 weeks after the last dose of study treatment intervention
9. Male participants with a partner of childbearing potential must agree to use adequate, medically approved contraceptive precautions during and for up to 6 weeks after the last dose of the study treatment intervention
10. Patient able and willing to provide written, informed consent for the study.

Exclusion criteria

1. Contraindication to the use of artesunate due to hypersensitivity
2. Pregnancy or lactation
3. Male or female participants unwilling to use an effective method of birth control (either hormonal in the form of contraceptive pill or barrier method of birth control accompanied by the use of a proprietary spermicidal foam/gel or film); or agreement of true abstinence from time to consent is signed until 6 weeks after the last dose of study treatment intervention (i.e. withdrawal, calendar, ovulation, symptothermal and post ovulation methods are not considered acceptable methods)
4. History of immunosuppression
5. History of hearing or balance problems
6. Weight \< 52kg or \> 110kg
7. Other planned intervention, apart from standard of care
8. Any other malignant disease diagnosis within the preceding 2 years with the exception of non-melanomatous skin cancer and carcinoma in situ
9. Lactose intolerance