Second-Line Treatment for Advanced Pancreatic Adenocarcinoma: Is There a Role for Gemcitabine?

Efficacy of gemcitabine plus nab-paclitaxel in second-line treatment of metastatic pancreatic cancer

Despite numerous studies on second-line therapies in metastatic pancreatic cancer, there is no randomized study evaluating the efficacy of gemcitabine plus nab-paclitaxel as a second-line treatment. This study aims to examine the efficacy of gemcitabine plus nab-paclitaxel in second-line therapy. In this retrospective study, a total of 218 patients from 23 centers were included. The primary endpoint was progression-free survival (PFS), secondary endpoints included overall survival (OS), treatment efficacy based on ECOG performance status (PS), and tumor marker (CEA, CA 19 - 9) levels. In the second-line treatment with gemcitabine plus nab-paclitaxel, the median PFS was 5.1 months (95% CI, 5.6 to 7.1), and the median OS was 8.6 months (95% CI, 7.3 to 10.0). Median PFS was 6.6 months in patients with normal CEA levels compared to 4.4 months in patients with high CEA levels (P = 0.01). Median PFS was 6 months in patients with ECOG PS 0-1 compared to 3.8 months in patients with PS 2 (P < 0.01). This study demonstrates the contribution of gemcitabine plus nab-paclitaxel in both OS and PFS in second-line treatment of metastatic pancreatic cancer. It was found to be a good option especially for young patients with good ECOG PS.

Predicting Tumor Volume Doubling Time and Progression-Free Survival in Untreated Patients from Patient-Derived-Xenograft (PDX) Models: A Translational Model-Based Approach

Tumor volume doubling time (TVDT) has been shown to be a potential surrogate marker of biological tumor activity. However, its availability in clinics is strongly limited due to ethical and practical reasons, as its assessment requires at least two subsequent tumor volume measurements in untreated patients. Here, a translational modeling framework to predict TVDT distributions in untreated cancer patient populations from tumor growth data in patient-derived xenograft (PDX) mice is proposed. Eleven solid cancer types were considered. For each of them, a set of tumor growth studies in PDX mice was selected and analyzed through a mathematical model to characterize the distribution of the exponential tumor growth rate in mice. Then, assuming an exponential growth of the tumor mass in humans, the growth rates were scaled from PDX mice to humans through an allometric scaling approach and used to predict TVDTs in untreated patients. A very good agreement was found between model predicted and clinically observed TVDTs, with 91% of the predicted TVDT medians fell within 1.5-fold of observations. Further, exploiting the intrinsic relationship between tumor growth dynamics and progression free survival (PFS), the exponential growth rates in humans were used to generate the expected PFS curves in absence of anticancer treatment. Predicted curves were extremely close to published PFS data from studies involving patient cohorts treated with supportive care or low effective therapies. The proposed approach shows promise as a potential tool to increase knowledge about TVDT in humans without the need of directly measuring tumor dimensions in untreated patients, and to predict PFS curves in untreated patients, that could fill the absence of placebo-controlled arms against which to compare treaded arms during clinical trials. However, further validation and refinement are needed to fully assess its effectiveness in this regard.

Gemcitabine + Nab-paclitaxel or Gemcitabine alone after FOLFIRINOX failure in patients with metastatic pancreatic adenocarcinoma: a real-world AGEO study

BACKGROUND

Gemcitabine (Gem) alone or with Nab-paclitaxel (Gem-Nab) is used as second-line treatment for metastatic pancreatic adenocarcinoma (mPA) after FOLFIRINOX (FFX) failure; however, no comparative data exist. This study evaluates the efficacy and safety of adding Nab-paclitaxel to Gem for mPA after FFX failure.

METHODS

In this retrospective real-world multicenter study, from 2011 to 2019, patients with mPA receiving Gem-Nab (Gem 1000 mg/m² + Nab 125 mg/m², 3 out of 4 weeks) or Gem alone were included after progression on FFX.

RESULTS

A total of 427 patients were included. Patients receiving Gem-Nab had more metastatic sites, peritoneal disease and less PS 2 (24% vs. 35%). After median follow-up of 22 months, Gem-Nab was associated with better disease control rate (DCR) (56% vs. 32%; P < 0.001), progression-free survival (PFS) (3.5 vs. 2.3 months; 95% CI: 0.43-0.65) and overall survival (OS) (7.1 vs. 4.7 months; 95% CI: 0.53-0.86). After multivariate analysis, Gem-Nab and PS 0/1 were associated with better OS and PFS. Grade 3/4 toxicity was more frequent with Gem-Nab (44% vs. 29%).

CONCLUSION

In this study, Gem-Nab was associated with better DCR, PFS and OS compared with Gem alone in patients with mPA after FFX failure, at the cost of higher toxicity.