The impact of checkpoint blockade therapy in making Hodgkin lymphoma sensitive to future treatment

The study evaluated whether exposure to checkpoint blockade therapy (CBT) can make relapsed/refractory (R/R) Hodgkin lymphoma (HL) sensitive to further treatments. The main finding was that CBT may make patients with R/R-HL responsive to further treatments.

While a large percentage of patients with HL can ve cured with current therapies, some patients become R/R. Relapse means cancer’s return after initial therapy. Refractory denotes cancer which fails to respond to treatment. Of these patients, only half are shown to respond to future treatments.

CBT such as nivolumab (Opdivo), pembrolizumab (Keytruda), or ipilimumab (Yervoy) makes the immune system identify and destroy cancer cells. CBT is effective against R/R-HL but sometimes stopped due to side effects or relapse. The success of further therapies in patients with R/R-HL after stopping CBT is unknown.

The study analyzed data of 81 adult patients with R/R-HL from 17 hospitals across the US and Canada. They were treated with CBT followed by further treatments. On average, patients had 4 therapies before receiving CBT. Drugs given as CBT included: nivolumab, pembrolizumab, ipilimumab, ipilimumab/nivolumab combination, and CA170. 65% of patients stopped CBT due to cancer progression. The overall response rate (ORR) to CBT was 56%. ORR signifies the proportion of patients whose tumor was reduced or destroyed by therapy.

On average, the following therapy was started after 49 days of CBT. 44% of patients received chemotherapy after CBT. 19% were given targeted therapy (TT). TT involved – brentuximab vedotin (Adcetris), ibrutinib (Imbruvica), and everolimus (Zortress).

ORR to further treatment was 62%. This included complete remission (CR) in 42% and partial remission (PR) in 20% of patients. CR defines complete absence and PR means partial disappearance of cancer symptoms. 12% of patients had stable disease (SD) meaning their cancer neither progressed nor reduced. 23% experienced progression.

Duration of response (DOR) means the time period when cancer responds to therapy with SD. The average DOR was 169 days for all patients. Among the 56% of patients who responded to CBT alone, 76% were responsive to further treatments. On average, patients survived for 6.3 months under without progression after treatment following CBT. The average overall survival on treatment following CBT was 21 months and was similar among all treatment types.

The authors concluded that even after relapsing on CBT, this treatment may make patients with R/R-HL sensitive to further therapy. 

This study was retrospective, meaning that it looked back in time to analyze patients’ data. Real-life clinical trials may be needed to prove this strategy’s effectiveness.