Real-world excess costs associated with hematologic adverse events (hAEs) during first-line (1L) treatment of metastatic pancreatic adenocarcinoma (mPDAC) with FOLFIRINOX (FFX), FFX without 5FU bolus, and gemcitabine+nab-paclitaxel (GnP).

693 Background: During 1L treatment of mPDAC with FFX and GnP, hAEs can harm patients (pts) and accrue excess costs to the health system, i.e., costs beyond those of a treated pt without the hAE. This study examined excess total cost of care (TCoC) and components (total inpatient; outpatient transfusion, granulocyte colony-stimulating factor [G-CSF], and thrombopoietic growth factor [TGF]) for three key hAEs (anemia, neutropenia, thrombocytopenia) during 1L FFX, FFX without 5FU bolus (FFXnb), and GnP. Methods: This retrospective observational study utilized Optum Market Clarity claims + EHR linked data. Inclusion criteria were: adult pts diagnosed with mPDAC between 1/1/2015 and 5/31/2023; initiated 1L FFX, FFXnb, or GnP within -14 to +90 days (index date); ≥6 months pre-index enrollment. hAEs during 1L were detected from lab values and grouped all grades combined. Pts were divided into “hAE groups” and “ref. groups” with and without any of the three hAEs of interest, respectively. Pts were matched 1:1 without replacement based on follow-up time. Costs were measured from the day a lab value indicated an hAE until 30 days later and during the corresponding times for ref. pts, then standardized to per-pt-per-month (PPPM). This study did not adjust for differences in pt characteristics. Results: Means and differences (95% CI) in TCoC following hAE detection for each regimen and hAE of interest are presented (Table). PPPM TCoC was greater for all three regimens and hAEs, driven by 1.6–4.9 times higher inpatient costs. Inpatient costs were $5,614 and $5,665 higher for FFX and FFXnb neutropenia pts vs. ref. groups. Use of outpatient G-CSF at any time during 1L was lower for FFX and FFXnb neutropenia pts, at 76% and 63% vs. 83% and 75% in the ref. groups, respectively. Outpatient TGF and transfusions were rare. Conclusions: All hAEs showed excess PPPM TCoC across regimens, driven by inpatient costs. FFX and FFXnb neutropenia pts had lower overall utilization of outpatient G-CSF but higher inpatient costs following detection of neutropenia, which may represent an opportunity for improved pt management. Excess TCoC of hAEs. AE (any grade) FFX, hAE group(N=199, 127, 157) FFX, ref. group(N=199, 127, 157) Diff. (95% CI) FFXnb, hAE group(N=202, 106, 137) FFXnb, ref. group (N=202, 106, 137) Diff. (95% CI) GnP, hAE group (N=406, 268, 270) GnP, ref. group (N=406, 268, 270) Diff. (95% CI) AnemiaTCoC, mean 30,561 22,310 8,251 (4,396–12,106) 31,866 23,380 8,487(4,007–12,966) 32,662 27,697 4,965(1,320–8,610) NeutropeniaTCoC, mean 30,382 24,952 5,430(-31–10,891) 26,588 22,571 4,017(-1,288–9,322) 32,975 31,051 1,924(-4,629–8,477) ThrombocytopeniaTCoC, mean 30,566 22,535 8,031 (3,895–12,166) 31,434 22,958 8,476(2,962–13,991) 33,863 30,751 3,113(-3,310–9,536)