Panitumumab in Combination With Radiotherapy in Patients With Locally Advanced RAS Wildtype Rectal Cancer (Clinical Stages II and III)

Study Overview
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Brief Summary
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The objective of this trial is to obtain evidence that, in patients with RAS wildtype tumors, a chemotherapy-free combined modality treatment with panitumumab is clearly superior to radiotherapy alone and achieves a pCR rate comparable to that after radiochemotherapy including two-drug combinations while reducing the toxicity compared to these two-drug regimens.

Official Title
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NEO-RIT - Panitumumab in Combination With Radiotherapy in Patients With Locally Advanced RAS Wildtype Rectal Cancer (Clinical Stages II and III)

Conditions
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Rectal Cancer

Intervention / Treatment
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* Drug: Panitumumab
* Radiation: Radiation of the pelvis


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Histologically confirmed diagnosis of locally advanced rectal cancer (stage II or III) localised 0 - 12 cm ab ano as measured by rigid rectoscopy (i.e. lower and middle third of the rectum) Staging requirements: trans-rectal endoscopic ultrasound (EUS) and magnetic resonance imaging (MRI) Sufficient representative sample material for RAS analysis Wild-type RAS (determined by an accredited local laboratory, if not available by pathology of Mannheim university) RAS wild-type tested in KRAS exon 2 (codons 12/13) KRAS exon 3 (codons 59/61) KRAS exon 4 (codons 117/146) NRAS exon 2 (codons 12/13) NRAS exon 3 (codons 59/61) NRAS exon 4 (codons 117/146) Informed consent of the patient Aged at least 18 years WHO Performance Status 0-2 Life expectancy of al least 12 weeks Adequate haematological, hepatic, renal and metabolic function parameters: Leukocytes > 3000/mm³ ANC ≥ 1500/mm³ Platelets ≥ 100,000/mm³ Hb > 9 g/dl Creatinine clearance ≥ 50 ml/min and serum creatinine ≤ 1.5 x upper limit of normal Bilirubin ≤ 1.5 x upper limit of normal GOT-GPT ≤ 2.5 x upper limit of normal AP ≤ 5 x upper limit of normal Magnesium ≥ lower limit of normal Calcium ≥ lower limit of normal Exclusion Criteria: Lower border of the tumor localised more than 12 cm ab ano as measured by rigid rectoscopy Distant metastases (to be excluded by CT scan of the thorax and abdomen) cT4 tumor (as determined by MRI and/or endorectal ultrasound) Risk of tumor involvement of the circumferential resection margin, according to the MRI assessment Sphincter sparing is the major reason for choosing the neoadjuvant treatment approach Prior antineoplastic therapy for rectal cancer Prior radiotherapy of the pelvic region Major surgery within the last 4 weeks prior to inclusion Subject pregnant or breast feeding, or planning to become pregnant within 6 months after the end of treatment Subject (male or female) is not willing to use highly effective methods of contraception (per institutional standard) during treatment and for 6 months (male or female) after the end of treatment (adequate: oral contraceptives, intrauterine device or barrier method in conjunction with spermicidal jelly) Serious concurrent diseases On-treatment participation in a clinical study in the period 30 days prior to inclusion Clinically significant cardiovascular disease in (incl. myocardial infarction, unstable angina, symptomatic congestive heart failure, serious uncontrolled cardiac arrhythmia) ≤ 1 year before enrolment History of interstitial lung disease, e.g. pneumonitis or pulmonary fibrosis or evidence of interstitial lung disease on baseline chest CT scan History of HIV infection Prior or concurrent malignancy (≤ 5 years prior to enrolment in study) except non-melanoma skin cancer or cervical carcinoma FIGO stage 0-1 if the patient is continuously disease-free Known allergic reactions on study medication

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Intervention/Treatment |
| --- |
|Drug: Panitumumab|Panitumumab 6 mg/kg BW will be administered IV every 2 weeks (q2w) on day -14, 1, 15, 29 (and 43, in case radiotherapy is still ongoing due to delays) of the radiotherapy.|
|Radiation: Radiation of the pelvis|Radiation is applied at single doses of 1.8 Gy at the ICRU 50 reference point, once daily, five times a week, adding up to 28 fractions over almost 6 weeks and a total reference dose of 50.4 Gy.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of pathological complete remissions | The rate of pathological complete remissions is determined after tumor resection following neoadjuvant treatment. | 15 weeks (average) after start of treatment (at surgery) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Toxicity according to NCI CTCAE |  |  | 
| Frequency of surgical morbidity and complications |  | Within four weeks after surgery | 
| pTNM findings in relation to initial cTNM staging |  | At surgery | 
| Regression grading according to Dworak |  | At surgery | 
| Clinical response rates (CR/PR/SD/PD) after neoadjuvant treatment |  | Before surgery | 
| Correlative biomarker analyses |  |  | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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RAS-Wildtype, Radiotherapy, Neoadjuvant treatment