Table 4. Overall survival and progression-free survival from start of first-line and second-line IO and chemotherapy by KRAS/STK11 mutation status (all patients).
| Immunotherapy | Chemotherapy | |||
|---|---|---|---|---|
| First-line therapy (n = 166) | Second-line therapy (n = 427) | First-line therapy (n = 1493) | Second-line therapy (n = 650) | |
| Median OS, months (IQR) | ||||
| KRASm/STK11m | 10.0 (7.3‒NA) | 6.9 (2.4‒21.9) | 11.7 (5.2‒23.5) | 11.3 (7.2‒25.2) |
| KRASwt/STK11wt | 16.3 (6.0‒29.6) | 12.0 (4.3‒26.9) | 18.2 (8.1‒38.4) | 13.2 (6.3‒33.5) |
| HR (95% CI) | 1.5 (0.7‒2.9)a | 1.6 (1.2‒2.3)b,c | 1.6 (1.3‒1.9)a,c | 1.3 (0.9‒1.8)b |
| Median PFS, months (IQR) | ||||
| KRASm/STK11m | 4.1 (2.5‒9.6) | 2.2 (1.5‒3.0) | 4.5 (2.1‒7.5) | 4.4 (2.8‒6.7) |
| KRASwt/STK11wt | 4.4 (2.1‒11.7) | 2.8 (1.7‒7.0) | 5.9 (2.8‒11.3) | 4.3 (2.2‒9.7) |
| HR (95% CI) | 1.3 (0.8‒2.2)a | 1.8 (1.4‒2.4)b,c | 1.4 (1.2‒1.7)a,c | 1.1 (0.8‒1.5)b |
OS and PFS were assessed as time to event from initiation of line of therapy (first-line or second-line). All HR values reported are adjusted HRs calculated using multivariate Cox regression models; the models included all patients, including those with KRASm/STK11wt and KRASwt/STK11m (total n = 270 [first-line immunotherapy]; 670 [second-line immunotherapy]; 2137 [first-line chemotherapy]; and 863 [second-line chemotherapy]). Variables in the final adjusted multivariate analysis
a Age at start of line 1, gender, smoking history, ECOG status ≤60 days before start of line 1, and stage at initial diagnosis.
b Age at start of line 2, gender, smoking history, ECOG status ≤60 days before start of line 2, stage at initial diagnosis, and first-line treatment type.
c p-value <0.005. CI: confidence interval; CT: chemotherapy; ECOG: Eastern Cooperative Oncology Group; HR: hazard ratio; IO: immunotherapy; IQR: interquartile range; m: mutant; OS: overall survival; PFS: progression-free survival; wt: wild type.