Table 2:
Multivariate analysis of the effect the platinum free interval on PFS (A) and OS (B) after re-exposure to platinum vs. non-platinum chemotherapy
| A) Progression Free Survival | ||||||
| Sequential Chemo IO | Concurrent ChemoIO | |||||
| Chemo ➔ IO ➔ Chemo N=546 | ChemoIO ➔ Chemo N=137 | |||||
| Variable | HR | 95% CI | p | HR | 95% CI | p |
| PB vs. non-PB | 1.36 | 0.97–1.9 | 0.08 | 1.37 | 0.69–2.8 | 0.37 |
| PFI ≥ 5 mo vs. < 5 mo | 0.76 | 0.58–1.0 | 0.04 | |||
| PFI ≥6 mo vs. <6 mo | 1.7 | 0.81–3.5 | 0.16 | |||
| Sex, male vs. female | 1.0 | 0.8–1.3 | 0.9 | 1.12 | 0.64–2 | 0.69 |
| Age diagnosis ≥70 vs. <70 yrs old | 0.88 | 0.7–1.1 | 0.3 | 0.86 | 0.5–1.6 | 0.62 |
| Race, white vs. non-white | 0.99 | 0.78–1.3 | 0.95 | 1.07 | 0.6 –1.95 | 0.8 |
| Kidney function | 0.96 | 0.8 –1.2 | 0.7 | 1.1 | 0.5 –2.6 | 0.85 |
| Among PFI long | PFI ≥ 5 mo | PFI ≥6 mo | ||||
| PB vs. non-PB | 0.8 | 0.6–1.1 | 0.2 | 0.6 | 0.2–1.8 | 0.4 |
| Among PFI short | PFI < 5 mo | PFI <6 mo | ||||
| PB vs. non-PB | 1.36 | 0.97–1.9 | 0.08 | 1.37 | 0.7 –2.8 | 0.37 |
| Among PB | ||||||
| PFI long vs short | 0.44 | 0.3–0.66 | 0.000 | 0.8 | 0.3–2.1 | 0.6 |
| Among non-PB | ||||||
| PFI long vs short | 0.76 | 0.6–0.99 | 0.043 | 1.7 | 0.8–4 | 0.2 |
| B) Overall Survival | ||||||
| Sequential Chemo IO | Concurrent ChemoIO | |||||
| Chemo ➔ IO ➔ Chemo N=546 | ChemoIO ➔ Chemo N=137 | |||||
| Variable | HR | 95% CI | p | HR | 95% CI | p |
| PB vs. non-PB | 0.88 | 0.65–1.2 | 0.4 | 1.17 | 0.65–2.1 | 0.6 |
| PFI ≥ 5 mo vs. < 5 mo | 0.64 | 0.5–0.8 | 0.000 | |||
| PFI ≥6 mo vs. <6 mo | 0.5 | 0.21–1.2 | 0.11 | |||
| Sex, male vs. female | 1.23 | 1.01–1.5 | 0.038 | 1.17 | 0.71–1.9 | 0.5 |
| Age diagnosis ≥70 vs. <70 yrs old | 1.2 | 0.99–1.5 | 0.067 | 1.1 | 0.67–1.9 | 0.7 |
| Race, white vs. non-white | 1.16 | 0.94–1.4 | 0.16 | 1.01 | 0.6–1.7 | 0.97 |
| Kidney function | 0.77 | 0.6–1 | 0.051 | 1.1 | 0.5–2.4 | 0.84 |
| Among PFI long | PFI ≥ 5 mo | PFI ≥6 mo | ||||
| PB vs. non-PB | 0.8 | 0.58–1.2 | 0.19 | 0.73 | 0.2–2.6 | 0.64 |
| Among PFI short | PFI < 5 mo | PFI <6 mo | ||||
| PB vs. non-PB | 0.88 | 0.65–1.2 | 0.4 | 1.17 | 0.65–2.1 | 0.6 |
| Among PB | ||||||
| PFI long vs short | 0.59 | 0.4–0.86 | 0.007 | 0.3 | 0.1–0.95 | 0.04 |
| Among non-PB | ||||||
| PFI long vs short | 0.64 | 0.5–0.8 | 0.000 | 0.5 | 0.21–1.2 | 0.11 |
Legend: Chemo = chemotherapy, IO= immunotherapy, ChemoIO= combination chemoimmunotherapy, yrs= years, HR= hazard ratio, CI= confidence interval. Kidney function was assessed by creatinine within 30 days of start of therapy. Subjects with missing values were excluded from the multivariate analysis (Sequential Chemo IO: 58, Concurrent ChemoIO: 10 patients excluded).