|Elimination half-life||∼9.4 days (range: 4-11 days)|
|Chemical and physical data|
|Molar mass||144324.12 g·mol−1|
|(what is this?)|
Panitumumab is manufactured by Amgen and marketed as Vectibix. It was originally developed by Abgenix Inc.
It was approved by the U.S. Food and Drug Administration (FDA) for the first time in September 2006, for "the treatment of EGFR-expressing metastatic colorectal cancer with disease progression" despite prior treatment. Panitumumab was approved by the European Medicines Agency (EMEA) in 2007, and by Health Canada in 2008 for "the treatment of refractory EGFR-expressing metastatic colorectal cancer in patients with non-mutated (wild-type) KRAS".
Panitumumab was the first monoclonal antibody to demonstrate the use of KRAS as a predictive biomarker.
Panitumumab was initially approved on September 27, 2006 for EGFR-expressing, metastatic CRC with disease progression on or following fluoropyrimidine-, oxaliplatin-, and irinotecan-containing regimens, based on the results of a study which showed clinical benefit in metastatic colorectal cancer patients. In July 2009, the FDA updated the labels of two anti-EGFR monoclonal antibody drugs (panitumumab and cetuximab) indicated for the treatment of metastatic colorectal cancer to include information about KRAS mutations. This was the result of a study, which demonstrated lack of benefit with Panitumumab in patients who carried NRAS mutations.
Panitumumab is an IgG2 human monoclonal antibody.
EGFR is a transmembrane protein. Panitumumab works by binding to the extracellular domain of the EGFR preventing its activation. This results in halting of the cascade of intracellular signals dependent on this receptor.
The pharmacokinetics (PK) of panitumumab shows the so-called target-mediated disposition behavior. However, the PK is approximately linear at clinical doses, and the terminal half-life for a typical male patient of 80 kg and 60 years of age with colorectal cancer is about 9.4 days.
Panitumumab has been associated with skin rash, fatigue, nausea, diarrhea, fever, and decreased magnesium levels. Often, skin rash is noted in the sun exposed parts of the body, such as the face or chest. Oral antibiotics may be needed for worsening skin rash, such as one accompanied with blisters and ulcers. Otherwise, topical steroid creams like hydrocortisone may help.
Ocular toxicity or keratitis was observed in 16% of patients on panitumumab, usually necessitating the discontinuance of therapy.
In clinical trials, 90% of patients had dermatological toxicities and 15% of those were severe. Because of this, panitumumab has a boxed warning cautioning patients. Skin toxicities were typically apparent two weeks after beginning treatment. More severe skin toxicities were associated with improved progression free survival and overall survival.
Pulmonary fibrosis and interstitial lung disease were observed in clinical trials.
Panitumumab does not work in patients who have KRAS or NRAS mutations.
Panitumumab was generated using Abgenix's XenoMouse platform technology, in which engineered mice were utilized to produce human antibodies. Abgenix partnered with Immunex Corporation to develop the antibody, and Amgen acquired Immunex in 2003. In 2006, Amgen acquired Abgenix as well. In 2013, Amgen formed an agreement with Zhejiang Beta Pharma to form Amgen Beta Pharmaceuticals and market panitumumab in China. Amgen and Takeda have an agreement under which Takeda will develop and commercialise panitumumab in Japan. Panitumumab is licensed to Dr Reddys Laboratories in India and GlaxoSmithKline in the UK.
Pantiumumab is being studied in numerous phase II and III clinical trials. Phase III clinical trials include treatment of esophageal cancer, urothelial carcinoma, metastatic head and neck cancer, and liver metastasis in colorectal cancer. Early trials showed limited efficacy in patients with malignant melanoma, bladder cancer, prostate cancer, and renal cell carcinoma.
Panitumumab vs. Cetuximab
Although they both target the EGFR, panitumumab (IgG2) and cetuximab (IgG1) differ in their isotype and they might differ in their mechanism of action. Monoclonal antibodies of the IgG1 isotype may activate the complement pathway and mediate antibody-dependent cellular cytotoxicity (ADCC). It is not clear at this time, if one drug is superior to the other. In one of the studies, both these drugs were noted to be similar in activity.
- "Illumina, Amgen to Develop CDx for Colorectal Cancer". News: Molecular Diagnostics. Gen. Eng. Biotechnol. News (paper). 34 (4). February 15, 2014. p. 32.
- "U.S. Food and Drug Administration" (PDF).
- Gibson, Tara Beers; Ranganathan, Aarati; Grothey, Axel (2006). "Randomized Phase III Trial Results of Panitumumab, a Fully Human Anti—Epidermal Growth Factor Receptor Monoclonal Antibody, in Metastatic Colorectal Cancer". Clinical Colorectal Cancer. 6 (1): 29–31. doi:10.3816/CCC.2006.n.01. PMID 16796788.
- "FDA updates Vectibix and Erbitux labels with KRAS testing info".[unreliable medical source?]
- Douillard, Jean-Yves; Oliner, Kelly S.; Siena, Salvatore; Tabernero, Josep; Burkes, Ronald; Barugel, Mario; Humblet, Yves; Bodoky, Gyorgy; Cunningham, David; Jassem, Jacek; Rivera, Fernando; Kocákova, Ilona; Ruff, Paul; Błasińska-Morawiec, Maria; Šmakal, Martin; Canon, Jean Luc; Rother, Mark; Williams, Richard; Rong, Alan; Wiezorek, Jeffrey; Sidhu, Roger; Patterson, Scott D. (2013). "Panitumumab–FOLFOX4 Treatment andRASMutations in Colorectal Cancer". New England Journal of Medicine. 369 (11): 1023–34. doi:10.1056/NEJMoa1305275. PMID 24024839.
- Plunkett, Jack W. (September 30, 2005). Plunkett's Biotech & Genetics Industry Almanac 2006. Plunkett Research. ISBN 978-1-59392-033-3.[page needed]
- Ma, Peiming; Yang, Bing-Bing; Wang, Yow-Ming; Peterson, Mark; Narayanan, Adimoolam; Sutjandra, Liviawati; Rodriguez, Rachelle; Chow, Andrew (2009). "Population Pharmacokinetic Analysis of Panitumumab in Patients with Advanced Solid Tumors". The Journal of Clinical Pharmacology. 49 (10): 1142–56. doi:10.1177/0091270009344989. PMID 19723673.
- Lacouture, M. E.; Mitchell, E. P.; Piperdi, B.; Pillai, M. V.; Shearer, H.; Iannotti, N.; Xu, F.; Yassine, M. (2010). "Skin Toxicity Evaluation Protocol with Panitumumab (STEPP), a Phase II, Open-Label, Randomized Trial Evaluating the Impact of a Pre-Emptive Skin Treatment Regimen on Skin Toxicities and Quality of Life in Patients with Metastatic Colorectal Cancer". Journal of Clinical Oncology. 28 (8): 1351–7. doi:10.1200/JCO.2008.21.7828. PMID 20142600.
- "Panitumumab - Amgen - AdisInsight".
- "Cisplatin and 5-FU +/- Panitumumab for Patients With Nonresectable,Advanced or Metastatic Esophageal Squamous Cell Cancer - Full Text View - ClinicalTrials.gov". clinicaltrials.gov.
- "I-MVAC +/- Panitumumab as First-line Treatment of Advanced Urothelial Carcinoma Without H-Ras Nor K-Ras Mutations - Full Text View - ClinicalTrials.gov". clinicaltrials.gov.
- "Study of Panitumumab Efficacy in Patients With Recurrent and/or Metastatic Head and Neck Cancer - Study Results - ClinicalTrials.gov". clinicaltrials.gov.
- "Treatment Strategies in Colorectal Cancer Patients With Initially Unresectable Liver-only Metastases - Full Text View - ClinicalTrials.gov". clinicaltrials.gov.
- HealthValue: IgG1 & IgG2[unreliable medical source?]
- Price, Timothy J; Peeters, Marc; Kim, Tae Won; Li, Jin; Cascinu, Stefano; Ruff, Paul; Suresh, Atilli Satya; Thomas, Anne; Tjulandin, Sergei; Zhang, Kathy; Murugappan, Swaminathan; Sidhu, Roger (2014). "Panitumumab versus cetuximab in patients with chemotherapy-refractory wild-type KRAS exon 2 metastatic colorectal cancer (ASPECCT): A randomised, multicentre, open-label, non-inferiority phase 3 study". The Lancet Oncology. 15 (6): 569–79. doi:10.1016/S1470-2045(14)70118-4. PMID 24739896.
- Amado, Rafael G.; Wolf, Michael; Peeters, Marc; Van Cutsem, Eric; Siena, Salvatore; Freeman, Daniel J.; Juan, Todd; Sikorski, Robert; Suggs, Sid; Radinsky, Robert; Patterson, Scott D.; Chang, David D. (2008). "Wild-Type KRAS is Required for Panitumumab Efficacy in Patients with Metastatic Colorectal Cancer". Journal of Clinical Oncology. 26 (10): 1626–34. doi:10.1200/JCO.2007.14.7116. PMID 18316791.
- Van Cutsem, Eric; Peeters, Marc; Siena, Salvatore; Humblet, Yves; Hendlisz, Alain; Neyns, Bart; Canon, Jean-Luc; Van Laethem, Jean-Luc; Maurel, Joan; Richardson, Gary; Wolf, Michael; Amado, Rafael G. (2007). "Open-Label Phase III Trial of Panitumumab Plus Best Supportive Care Compared with Best Supportive Care Alone in Patients with Chemotherapy-Refractory Metastatic Colorectal Cancer". Journal of Clinical Oncology. 25 (13): 1658–64. doi:10.1200/JCO.2006.08.1620. PMID 17470858.