Trial results for the NEO-SPACE study (NCT03734809) investigating pembrolizumab (Keytruda) in nasopharyngeal cancer were posted on ClinicalTrials.gov on 2025-12-24. The study reported a two-year progression-free survival of 73.8% and high patient tolerability, with no Grade 4 mucositis/skin reactions or Grade 5 adverse events related to treatment.
Trial design
The NEO-SPACE trial (NCT03734809) is an open-label, single-arm, non-randomized, multi-site, Phase 2 clinical trial that enrolled 43 participants. The study investigated a multi-part treatment regimen for previously untreated Stage IVA nasopharyngeal cancer (NPC). This regimen included neoadjuvant pembrolizumab in combination with gemcitabine-cisplatin for 2 cycles, followed by concurrent pembrolizumab-cisplatin-radiation, and then maintenance pembrolizumab monotherapy given every 3 weeks for a total treatment duration of 12 months. The primary outcomes for the study were not explicitly detailed in the posted results.
Key results
The trial results provided several key measurements for the pembrolizumab treatment group:
- Two-year Progression Free Survival was 73.8 percentage of participants.
- Regarding safety, 0 participants experienced Grade 4 Mucositis/Skin Reaction or Any Grade 5 Adverse Event assessed as definitely, probably, or possibly related to protocol treatment during the first year.
- Similarly, 0 participants experienced Grade 4 Mucositis/Skin Reaction or Any Grade 5 Adverse Event assessed as definitely, probably, or possibly related to protocol treatment occurring after the first year.
- Patient tolerability to the neoadjuvant component of the protocol treatment regimen was 98.0 percentage of participants.
- Patient tolerability to the concurrent component of the protocol treatment regimen was 73.1 percentage of participants.
- Patient tolerability to the maintenance component of the protocol treatment regimen was 100.0 percentage of participants.
- Other ≥ Grade 3 Adverse Events were reported in 32.4 percentage of participants (for one measurement), 29.7 percentage of participants (for a second measurement), and 29.7 percentage of participants (for a third measurement).
What this means
The NEO-SPACE trial results indicate that the multi-component regimen involving pembrolizumab shows a promising two-year progression-free survival rate of 73.8% in patients with previously untreated Stage IVA nasopharyngeal cancer. The absence of Grade 4 mucositis/skin reactions or any Grade 5 adverse events directly related to the protocol treatment, combined with high patient tolerability (98.0% for neoadjuvant, 73.1% for concurrent, and 100.0% for maintenance), suggests a favorable safety and tolerability profile. These Phase 2 single-arm findings offer important data for pembrolizumab's potential role in this aggressive cancer.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT03734809, titled "NEO-SPACE Trial: Pembrolizumab and Chemoradiation in Nasopharyngeal Cancer," were posted on 2025-12-24 on clinicaltrials.gov.