Treatment Outcomes and Prognostic Factors of Gemcitabine Plus Nab-Paclitaxel as Second-Line Chemotherapy after Modified FOLFIRINOX in Unresectable Pancreatic Cancer

Prognostic analysis and outcomes of metastatic pancreatic cancer patients receiving nab-paclitaxel plus gemcitabine as second or later-line treatment

BACKGROUND

Pancreatic cancer (PC) first-line therapy often consists of polychemotherapy regimens, but choosing a second-line therapy after disease progression, especially following first-line FOLFIRINOX, remains a clinical challenge. This study presents results from a large, multicenter, retrospective analysis of Italian patients with metastatic PC (mPC) treated with Nab-paclitaxel/Gemcitabine (AG) as second or later line of treatment. Main objective of the study is to identify prognostic factors that could inform treatment decisions.

METHODS

The study included 160 mPC patients treated with AG in 17 Italian institutions. AG was administered according to labelling dose, until disease progression, unacceptable toxicity or patient refusal. Variations in schedules, dose modifications, supportive measures, and response evaluation were determined by individual clinicians' practice.

RESULTS

AG was well-tolerated and exhibited promising clinical activity. The overall response rate (ORR) and the disease control rate (DCR) were 22.5% and 45.6%, respectively. Median progression-free survival (PFS) and overall survival (OS) were 3.9 and 6.8 months, respectively. Among the patients who received AG as a second-line therapy (n = 111, 66.9%), median PFS and OS were 4.2 and 7.4 months, respectively. Notably, in the 76 patients (68%) receiving AG after first-line FOLFIRINOX, an ORR of 19.7% and a DCR of 46.0% were observed, resulting in a median PFS of 3.5 and median OS of 5.7 months. The study identified specific clinical or laboratory parameters (LDH, NLR, fasting serum glucose, liver metastases, ECOG PS, and first-line PFS) as independent prognostic factors at multivariate level. These factors were used to create a prognostic nomogram that divided patients into three risk classes, helping to predict second-line OS and PFS.

CONCLUSIONS

This study represents the largest real-world population of mPC patients treated with AG as a second or later line of therapy. It supports the feasibility of this regimen following first-line FOLFIRINOX, particularly in patients with specific clinical and laboratory characteristics who derived prolonged benefit from first-line therapy.

Translational PK-PD/TD modeling of antitumor effects and peripheral neuropathy in gemcitabine and nab-paclitaxel chemotherapy from xenograft mice to patients for optimal dose and schedule

PURPOSE

Gemcitabine and nab-paclitaxel (GnP) treatment, the standard first-line chemotherapy for unresectable pancreatic cancer, often causes peripheral neuropathy (PN). To develop alternative dosing strategies to avoid severe PN, understanding the relationship between pharmacokinetics (PK) and pharmacodynamics/toxicodynamics (PD/TD) is necessary. We established a PK-PD/TD model of GnP treatment to develop an optimal dose schedule.

METHODS

A mouse xenograft model of human pancreatic cancer was generated to measure drug concentrations in the plasma and tumor, antitumor effects, and PN after GnP treatment. The Simeoni tumor growth inhibition model with tumor concentrations and empirical indirect response models were used for the PD and TD models, respectively. Clinical outcomes were predicted with reported population estimates of PK parameters in cancer patients.

RESULTS

The PK-PD/TD model simultaneously described the observed tumor volume and paw withdrawal frequency in the von Frey test. For the standard GnP regimen, the model predicted clinical overall response (75.1%), which was overestimated compared to that in a recent phase II study (42.1%) but lower than the observed disease control rate (96.5%). Model simulation showed that dose reduction to less than 40% GnP dose was not effective; a change of dose schedule from every week for 3 weeks to every 2 weeks was a more favorable approach than dose reduction to 60% every week.

CONCLUSION

The PK-PD/TD model-based translational approach provides a guide for optimal dose determination to avoid severe PN while maintaining antitumor effects during GnP chemotherapy. Further research is needed to enhance its applicability and potential for combination chemotherapy regimens.