George Kim, MD:After patients have been treated with gemcitabine-based therapy; typically gemcitabine and nab-paclitaxel; we have to think about second-line therapies. There is a very important regimen that is available. It’s called the Nal-IRI regimen. It’s nanoparticle liposomal irinotecan which is combined with infusional 5-FU and leucovorin. Now, this Nal-IRI drug is very intriguing in, that it has more favorable pharmacology than irinotecan by itself. What am I speaking of, 80,000 molecules are in a liposome, that it circulates throughout the body for up to 1 week; 95% of the irinotecan stays in the liposome, allowing the half-life of irinotecan and its active metabolite, SN-38, to increase by 4-fold.
Data shows that with nanoparticle liposomal irinotecan, there’s about a 50-fold higher exposure, compared to regular irinotecan. This translates to about a 5-fold difference in the actual tumor with the liposomal formulation versus regular irinotecan, that then translates into radioactivity in preclinical mouse models, which then translates into a survival benefit in a clinical trial called the NAPOLI-1 study. This was a randomized prospective global phase III study that showed survival of 6.1 months versus 4.2 months, and had a 2-month delta in the second line, which is the standard in GI cancers. That has become a regimen that we’ve accepted in the second-line post-gemcitabine use.
What you have then is, and this is according to the National Comprehensive Cancer Network or NCCN, is the category 1 recommendation that patients are given gemcitabine-based therapy in the frontline progress, or proceed to 5-FUbased therapy in the second-line. You would give a patient gemcitabine/nab-paclitaxel when the tumor progresses or they develop toxicities such as neuropathy or thrombocytopenia. Then you would go on to 5-FU–based therapy; that being 5-FU combined with Nal-IRI showing survival benefit, FDA approved, category 1 recommendation. It does not have similar toxicities to the first-line regimen. Again, the neuropathy and thrombocytopenia are not observed with the second-line therapy.
Alternatively, if you were to choose a 5-FUbased therapy, FOLFIRINOX in the frontline, what do you do in the second line? Because the patients typically come off with residual neuropathy. Are you going to use gemcitabine/nab-paclitaxel? It’s difficult to do due to the neuropathy, and also thrombocytopenia that is observed with this first-line regimen. That is why that first sequence is so attractive and becoming more and more used; gemcitabine/nab-paclitaxel followed by 5-FU/Nal-IRI in the second-line setting.
Transcript edited for clarity.
A 57-Year-Old Man With Abdominal Pain and Unexplained Weight Loss
KEYNOTE-859 Outcomes Influence NCCN Guidelines on Pembrolizumab in Upper GI Cancer
April 10th 2024During a Case-Based Roundtable® event, David Zhen, MD, discussed how treatment of upper gastrointestinal cancer with pembrolizumab and chemotherapy is impacted by PD-L1 composite positive score, in the second article of a 2-part series.
Read More
The Impact of the Gut Microbiome in Young Patients With Colorectal Cancer
February 15th 2021In season 2, episode 2 of Targeted Talks, Cathy Eng, MD, speaks with Benjamin Weinberg, MD, about the gut microbiome, and how the presence of certain microbiota impact the onset and intensity of disease as well as the potential response to certain treatments.
Listen