InterAACT
InterAACT was the first randomised trial ever run in advanced anal cancer; the two chemotherapy pairs shrank tumours equally often, but carboplatin with paclitaxel caused far fewer serious side effects and patients on it lived longer, so it became the standard chemotherapy backbone.
Overview
InterAACT was an international randomised phase 2 trial of the International Rare Cancers Initiative, led from the Royal Marsden with ECOG-ACRIN, AGITG and EORTC partners, in 91 patients with chemotherapy-naive advanced anal squamous cell carcinoma randomised to cisplatin plus fluorouracil or carboplatin plus weekly paclitaxel. The primary endpoint was best overall response rate by 24 weeks.
Response rates were the same (57 against 59 percent), but serious adverse events were more frequent with cisplatin-fluorouracil (62 against 36 percent), median progression-free survival was 5.7 against 8.1 months and median overall survival 12.3 against 20 months (hazard ratio 2.00 for cisplatin-fluorouracil). Carboplatin-paclitaxel became the reference regimen and the chemotherapy backbone of POD1UM-303, which is how the corpus's metastatic anal cancer page cites it.
- 59 vs 57 out of 100 had their tumour shrink with Carboplatin + weekly paclitaxel compared with Cisplatin + fluorouracil; 2 more per 100.
- Roughly one extra person helped for every 50 treated. That is a rough figure taken from the two percentages, not a guarantee for any one person.
- A response rate counts how many people had their tumours shrink by a set amount; shrinking is encouraging but does not by itself show that people live longer or feel better.
- Median 20 vs 12.3 months with Carboplatin + weekly paclitaxel compared with Cisplatin + fluorouracil; about 7.7 months longer for half the group.
- A median is a midpoint: half the people did better than this and half did worse, so it is not a prediction for any one person.
- Put another way, the treated group had about 100 percent higher chance of the event at any given time (hazard ratio 2, likely range 1.15 to 3.47).
- Overall survival counts deaths from any cause, so it is the most direct measure of whether a treatment helps people live longer.
- Median 8.1 vs 5.7 months with Carboplatin + weekly paclitaxel compared with Cisplatin + fluorouracil; about 2.4 months longer for half the group.
- A median is a midpoint: half the people did better than this and half did worse, so it is not a prediction for any one person.
- This is a surrogate endpoint: it measures the cancer being controlled or absent on scans and tests, which often, but not always, translates into living longer.
- 36 vs 62 out of 100 reached this endpoint with Carboplatin + weekly paclitaxel compared with Cisplatin + fluorouracil; 26 fewer per 100.
- Roughly one extra person helped for every 4 treated. That is a rough figure taken from the two percentages, not a guarantee for any one person.
- The p-value (0.016) says a difference this large would rarely happen by chance; it does not say how large or how useful the difference is.
- This endpoint is not one of the standard survival or response measures; read it alongside the trial's primary result.
- These results apply to the people the trial enrolled: Chemotherapy-naive inoperable locally recurrent or metastatic anal squamous cell carcinoma at 60 centres through the International Rare Cancers Initiative: cisplatin plus fluorouracil against carboplatin plus weekly paclitaxel, with best overall response rate by 24 weeks as the primary endpoint. People in a different situation may not see the same effect.
- Only 91 people took part, so the numbers are less certain than in a large trial.
Numbers are from the trial as recorded here; see the source links in the table below. This is orientation, not medical advice: ask your team how closely the trial population matches you.
91 randomised.
95% CI 42.1 to 74.4 · 95% CI 39.4 to 73.7
Source95% CI 12.7 to not reached · 95% CI 9.2 to 17.7
Source| Endpoint | Arm | n | Value | HR (95% CI) | p | Source |
|---|---|---|---|---|---|---|
| Best overall response rate by 24 weeksprimary | Carboplatin + weekly paclitaxel | 45 | 59% | - | - | link |
| Cisplatin + fluorouracil | 46 | 57% | ||||
| Overall survival | Carboplatin + weekly paclitaxel | 45 | 20 months | 2 (1.15 to 3.47) | 0.014 | link |
| Cisplatin + fluorouracil | 46 | 12.3 months | ||||
| Progression-free survival | Carboplatin + weekly paclitaxel | 45 | 8.1 months | - | - | link |
| Cisplatin + fluorouracil | 46 | 5.7 months | ||||
| Serious adverse events | Carboplatin + weekly paclitaxel | 45 | 36% | - | 0.016 | link |
| Cisplatin + fluorouracil | 46 | 62% |
Similar pages
not linked directly; found by shared links- TrialPOD1UM-303/InterAACT-2
Shares Metastatic and recurrent anal squamous cell carcinoma, Anal cancer (squamous cell carcinoma), Paclitaxel / nab-paclitaxel, Carboplatin and the tag soc-trials.
- TrialInPACT
Shares ECOG-ACRIN Cancer Research Group, Paclitaxel / nab-paclitaxel, Cisplatin, Cytotoxic chemotherapy and the tag soc-trials.
- TrialSIOPEL-4
Shares Cisplatin, Carboplatin, Cytotoxic chemotherapy and the tag soc-trials.
- TrialNCI9673
Shares Metastatic and recurrent anal squamous cell carcinoma, Anal cancer (squamous cell carcinoma) and the tag soc-trials.
- TrialANCHOR
Shares Anal cancer (squamous cell carcinoma), Fluorouracil (5-FU) and the tag soc-trials.
- TrialAGCT1531
Shares Cisplatin, Carboplatin, Cytotoxic chemotherapy and the tag soc-trials.
- TrialGETUG 13
Shares Paclitaxel / nab-paclitaxel, Cisplatin, Cytotoxic chemotherapy and the tag soc-trials.
- TrialBALLAD
Shares Fluorouracil (5-FU), Cytotoxic chemotherapy and the tag soc-trials.