Efficacy and safety of FOLFIRI/aflibercept (FA) in an elderly population with metastatic colorectal cancer (mCRC) after failure of an oxaliplatin-based regimen

Maintenance with 5-FU/LV-aflibercept after induction with FOLFIRI-aflibercept versus FOLFIRI-aflibercept until progression as second-line treatment in older adults with metastatic colorectal cancer: the AFEMA phase II randomized trial

BACKGROUND

The combination chemotherapy i.v. 5-fluorouracil (5-FU), irinotecan, and aflibercept (FOLFIRI-A) is a standard second-line treatment of metastatic colorectal cancer (mCRC). The aim was to assess maintenance treatment in second-line setting in older patients (aged ≥70 years) with mCRC.

PATIENTS AND METHODS

We evaluated FOLFIRI-A given for six cycles followed by maintenance with 5-FU/leucovorin (LV)-A (arm A) or FOLFIRI-A (arm B) until progression in older adults with mCRC in the AFEMA randomized, open-label, non-inferiority phase II trial (EudraCT2016-004076-21/NCT03279289). Patients aged ≥70 years who previously failed oxaliplatin-fluoropyrimidine were randomly allocated (1 : 1) to either arm A (experimental) or arm B (control). After enrolling 35 patients, the FOLFIRI dose was reduced to level 1 in both arms due to toxicity. The primary endpoint was median progression-free survival (PFS); and secondary endpoints were median overall survival, objective response rate, and safety. Non-inferiority required the upper confidence interval (CI) limit to not exceed a hazard ratio (HR) of 1.5 (one-sided α = 0.075, 80% power).

RESULTS

A total of 170 patients were randomly allocated to arm A or arm B (n = 85 each). The median follow-up was 12.2 versus 10.9 months in arm A versus arm B. Most patients died (83.5% versus 88.2% in arm A versus arm B), mainly from disease progression. PFS non-inferiority was met (HR = 0.78, 95% CI 0.566-1.076, P = 0.131) with a median PFS of 6.1 versus 5.5 months in arm A versus arm B. Median overall survival was similar in arms A and B (12.2 and 11.5 months, respectively) (HR = 0.89, 95% CI 0.640-1.227, P = 0.467). During the maintenance phase, severe asthenia (4.5% versus 21.6%, P = 0.038), serious adverse events (SAEs) (17.8% versus 37.8%, P = 0.049), and treatment-related SAEs (6.7% versus 10.8%, P = 0.695) were reduced in arm A versus arm B.

CONCLUSION

In older adults, induction with six cycles of FOLFIRI-A plus maintenance with 5-FU/LV-A was non-inferior to FOLFIRI-A until progression. Severe asthenia, SAEs, and treatment-related SAEs were reduced with 5-FU/LV-A maintenance.

Maackia amurensis seed lectin (MASL) and soluble human podoplanin (shPDPN) sequence analysis and effects on human oral squamous cell carcinoma (OSCC) cell migration and viability

Maackia amurensis lectins serve as research and botanical agents that bind to sialic residues on proteins. For example, M. amurensis seed lectin (MASL) targets the sialic acid modified podoplanin (PDPN) receptor to suppress arthritic chondrocyte inflammation, and inhibit tumor cell growth and motility. However, M. amurensis lectin nomenclature and composition are not clearly defined. Here, we sought to definitively characterize MASL and its effects on tumor cell behavior. We utilized SDS-PAGE and LC-MS/MS to find that M. amurensis lectins can be divided into two groups. MASL is a member of one group which is composed of subunits that form dimers, evidently mediated by a cysteine residue in the carboxy region of the protein. In contrast to MASL, members of the other group do not dimerize under nonreducing conditions. These data also indicate that MASL is composed of 4 isoforms with an identical amino acid sequence, but unique glycosylation sites. We also produced a novel recombinant soluble human PDPN receptor (shPDPN) with 17 threonine residues glycosylated with sialic acid moieties with potential to act as a ligand trap that inhibits OSCC cell growth and motility. In addition, we report here that MASL targets PDPN with very strong binding kinetics in the nanomolar range. Moreover, we confirm that MASL can inhibit the growth and motility of human oral squamous cell carcinoma (OSCC) cells that express the PDPN receptor. Taken together, these data characterize M. amurensis lectins into two major groups based on their intrinsic properties, clarify the composition of MASL and its subunit isoform sequence and glycosylation sites, define sialic acid modifications on the PDPN receptor and its ability to act as a ligand trap, quantitate MASL binding to PDPN with KD in the nanomolar range, and verify the ability of MASL to serve as a potential anticancer agent.