In the battle against prostate cancer, Johnson & Johnson is getting off to a slow start in the PARP inhibitor competition.
EMA’s drug assessors have advised that the combo of Zejula and Zytiga be approved for use in treating metastatic castration-resistant prostate cancer (mCRPC). After the anticipated approval from the European Commission, however, the medicine combination will only be made accessible to people whose tumors have BRCA1/2 mutations. Prostate cancer medications Zytiga and Zejula are owned by Johnson & Johnson, which intends to launch a fixed-dose mixture of both treatments under the brand name Akeega. In addition, GSK has the rights to use Zejula for all additional indications.
Compared to the prostate cancer usage of AstraZeneca and Merck’s competitor PARP inhibitor, Lynparza, in their own Zytiga combination, the EMA’s proposed scope for Akeega is substantially limited. In December, Lynparza and Zytiga were given unrestricted approval to treat mCRPC by the European Commission. Research published in the Journal of Oncology found that only around one-third of instances of metastatic prostate cancer contain HRR gene modifications, with BRCA1/2 mutations making up roughly half of that category.
Clinical trial data for the combination medication is what really holds Akeega back. The drug did not outperform Zytiga monotherapy in individuals with mCRPC who lacked HRR changes in the phase 3 MAGNITUDE trial. Patients with tumors that harbored HRR mutations benefited the most from the combination treatment, with a 27% reduction in the risk of progression of the disease or fatality.
Subgroup analysis demonstrated that people with BRCA mutations drove the benefit alone. Nevertheless, evidence reported at the last ASCO GU conference showed that the medication had no beneficial effects on patients with additional HRR mutations.
The BRCA-mutated populace once again had better outcomes than their counterparts, according to a new analysis presented at this year’s American Society of Clinical Oncology Genitourinary (ASCO GU) Cancers Symposium. Long-term data analysis showed a trend toward improved survival for individuals using Akeega in the BRCA-positive sample, with a 12% reduction in mortality risk. The larger HRR-positive group did not fare any better in terms of survival.
Lynparza, when combined with Zytiga, reduced the risk of progress or fatality by nearly 35%, independent of HRR status in the phase 3 PROpel study. Among those with HRR mutations, the rate of improvement was 46%. Overall, the combination of Lynparza and Zytiga lowered the risk of mortality by 19% in all patients, according to the final overall survival study presented at this year’s ASCO GU conference. However, this reduction was not statistically significant.
Lynparza and Akeega will probably square off against a new mCRPC rival. Pfizer has recently announced that its PARP inhibitor regimen combining Talzenna and Xtandi had the longest median advancement-free survival in mCRPC. All patients in a phase 3 study benefited from the combination, irrespective of mutation status. Pfizer’s application for that purpose has been given priority evaluation by the FDA, and a decision is likely to be made this year.
In the meantime, the FDA postponed making a judgment on AZ’s application for Lynparza in mCRPC for three months back in December so that it could conduct a more thorough study. Furthermore, according to J&J’s 2022 annual securities report, the company still hadn’t even submitted the Akeega regimen to the FDA by that year’s end.
