AbbVie announced positive top-line results from IMMhance, the fourth pivotal Phase 3 clinical trial evaluating risankizumab (150 mg) for the treatment of patients with moderate to severe plaque psoriasis.
There were two phases in this study. Results from the first phase showed that after 16 weeks of treatment, risankizumab met the co-primary endpoints of at least a 90 percent improvement in the Psoriasis and Severity Index (PASI 90) and a static Physician Global Assessment (sPGA) score of clear or almost clear (sPGA 0/1) versus placebo. In the second phase of this study, the primary endpoint of sPGA 0/1 at week 52 (one year) was also met. The second phase (week 28 through 104) is evaluating the efficacy and safety of continuous therapy with risankizumab versus randomized withdrawal. Subsequently, retreatment is also being evaluated in this ongoing study. Risankizumab is not approved by regulatory authorities and its safety and efficacy have not been established.
"These positive results are consistent with the previous data we have seen with risankizumab throughout the pivotal Phase 3 clinical trial program," said Michael Severino, M.D., executive vice president, research and development and chief scientific officer, AbbVie. "With a significant portion of risankizumab patients achieving high levels of skin clearance, these results add to the data supporting risankizumab's potential to be an impactful new treatment option for patients living with psoriasis. We look forward to sharing additional data from the pivotal trial program with the scientific community and regulatory authorities as we prepare to move forward with global regulatory submissions."
Risankizumab is part of a collaboration with Boehringer Ingelheim, with AbbVie leading future development and commercialization of risankizumab globally. Top-line results of the three other risankizumab Phase 3 psoriasis pivotal trials (ultIMMa-1, ultIMMa-2 and IMMvent) were previously announced in October 2017.
At week 16, results from the IMMhance study showed that 73 percent of patients receiving risankizumab achieved PASI 90 compared to 2 percent of patients receiving placebo. An sPGA 0/1 was achieved by 84 percent of risankizumab patients compared to 7 percent of placebo patients.
Results showed that nearly half (47 percent) of patients receiving risankizumab achieved PASI 100 compared to 1 percent of patients receiving placebo. Additionally, 46 percent of patients receiving risankizumab achieved an sPGA 0 compared to 1 percent of patients receiving placebo. All primary and ranked secondary endpoints achieved p-values of <0.001 versus placebo.
In the second phase of the study (week 28 through week 104), patients originally randomized to risankizumab who achieved sPGA 0/1 at week 28 were re-randomized to risankizumab (maintenance) or placebo (withdrawal). Beginning at week 32, any patient who experienced a relapse (defined as an sPGA score of moderate to severe [>3]) was retreated with risankizumab immediately, four weeks later and every 12 weeks thereafter.
The primary endpoint of the second phase of the study (week 28 through week 104) was sPGA 0/1 at one year (week 52). Among the maintenance group, 87 percent of patients maintained sPGA 0/1 at one year compared to 61 percent of patients in the withdrawal group (p-value of <0.001).
The safety profile in IMMhance was consistent with previously reported Phase 3 clinical trials, with no new safety signals detected across the Phase 3 program. In this study, serious adverse events occurred in 2 percent of patients in the risankizumab group and 8 percent of patients in the placebo group through week 16. In the second part of the study until the data was locked, serious adverse events occurred in 6 percent of patients re-randomized to the risankizumab group and 6 percent of patients re-randomized to the placebo group. In the second phase of the study, one patient receiving risankizumab had intestinal adenocarcinoma and metastatic hepatic cancer and died on study day 339. A second patient treated with risankizumab died on study day 263 due to an unknown cause that was adjudicated as a major adverse cardiovascular event (MACE). There were two additional adjudicated MACE cases at the time of database lock. One event occurred in the placebo arm in the first phase of the study and the other occurred in the risankizumab arm in the second phase. All three patients had a past history of cardiovascular risk factors.
AbbVie is continuing to evaluate the potential of risankizumab across several immune-mediated conditions.
The IMMhance study is an ongoing Phase 3, multicenter, randomized, double-blind, placebo-controlled study designed to evaluate the safety and efficacy of risankizumab compared to placebo in adult patients with moderate to severe plaque psoriasis. In the first phase, patients were randomized 4:1 to risankizumab (150 mg), given as a subcutaneous injection at baseline, 4 weeks later and every 12 weeks thereafter, or placebo. The co-primary endpoints were achievement of at least a 90 percent improvement in the PASI score (PASI 90) and achievement of an sPGA 0/1 at week 16 compared to placebo. Patients who were originally randomized to placebo switched to risankizumab at week 16.
In the second phase of this study (week 28 through week 104), patients originally randomized to risankizumab who achieved sPGA 0/1 at week 28 were re-randomized to risankizumab (maintenance) or placebo (withdrawal). Beginning at week 32, any patient who experienced a relapse (defined as an sPGA moderate to severe [>3]) was retreated with risankizumab immediately, four weeks later and every 12 weeks thereafter. The primary endpoint from week 28 through week 104 of the study was sPGA 0/1 at one year. This Phase 3 study has been conducted in cooperation between AbbVie and Boehringer Ingelheim. The trial is ongoing and will evaluate patients up to 104 weeks.