Abstract 1444P
Background
As previously reported (ASCO 2020), PCA titration provides faster analgesic effect and higher patient satisfaction than non-PCA for severe cancer pain; however, optimal analgesic maintenance after the successful titration was unknown.
Methods
Subjects with persistent severe (NRS ≥ 7/10 at rest) cancer pain controlled with 24h IV HM-PCA titration were randomly assigned to 1 of 3 treatment arms: (A1) IV-HM-PCA with bolus-only where dose 10%-20% of total equianalgesic over the previous 24h (TEOP24H) administrated as needed; (A2) IV-HM-PCA with continuous infusion where dose was TEOP24H divided by 24 and bolus dosage for breakthrough pain was 10%-20% of TEOP24H; or (B) oral sustained-released morphine with TEOP24H/2×75% Q 12h and immediate-release morphine with 10%-20% of TEOP24H for breakthrough pain. Opioid dose was adjusted once every 24h. Primary endpoint is the sum of 24h average NRS Days 1-3 (3DNRS) divided by 3.
Results
Across 9 study sites, 95 subjects were randomly assigned: A1=30; A2=32; B=33. The predominant cancers were: colorectal (21.1%); lung (14.74%); and stomach (12.6%). The median 3DNRS (P25, 75) were 2.50 (2.08, 3.00) in A1, 2.42 (2.00, 2.67) in A2, and 3.33 (3.00, 4.00) in B, P <0.001. Daily NRS and patient satisfaction score (PSS, 0=most unsatisfaction and 10=most satisfaction) at day 0 were not significantly different. D1-D6 daily NRS and D3/D6 PSS were worse in B (Table). Equivalent morphine consumption (EMC) increase ([maximal daily EMC – D0 EMC]/D0 EMC) was significantly lower in A1 (Table). No severe adverse event occurred in any arm. Table: 1444P
| Median(P25,P75) | Day | A1 (n=30) | A2 (n=32) | B (n=33) | P |
| NRS | 0 | 4 (3, 4) | 4 (3, 4) | 4 (3, 4) | 0.61 |
| 1 | 3 (2, 3) | 3 (2, 3) | 4 (3, 4) | 0.003 | |
| 2 | 2.5 (2, 3) | 2 (2, 2.25) | 3 (3, 4) | < 0.001 | |
| 3 | 2 (2, 3) | 2 (2, 2.25) | 3 (3, 4) | < 0.001 | |
| 4 | 2 (2, 3) | 2 (2, 3) | 3 (2, 3.75) | 0.004 | |
| 5 | 2 (2, 3) | 2 (2, 3) | 3 (2, 3) | 0.027 | |
| 6 | 2 (2, 3) | 2 (2, 3) | 3 (2, 3) | 0.001 | |
| EMC increase | 0.10 (0.00, 0.31) | 0.26 (0.10, 0.81) | 0.25 (0.10, 0.40) | 0.024 | |
| PSS | 0 | 8 (6.25, 8) | 8 (7, 9) | 7 (6, 8.25) | 0.44 |
| 3 | 9 (8, 9) | 9 (8, 9) | 7 (6, 8) | < 0.001 | |
| 6 | 8 (7, 9) | 9 (8, 9) | 7 (7, 8) | < 0.001 |
Conclusions
IV-HM-PCA improves analgesia maintenance of severe cancer pain after successful titration compared to oral morphine and, without continuous infusion, may consume less opioid; a phase III trial of A1 vs. A2 is ongoing.
Clinical trial identification
NCT04243954.
Editorial acknowledgement
The authors wish to acknowledge Caron Modeas, Evolved Editing, LLC, for editorial assistance.
Legal entity responsible for the study
R. Lin.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.