Biotech Values

[DewDiligence]

Will D-Mab Be Better Than Zometa in Prostate Cancer?

[This an analyst’s report from Citi (c/o ‘mopgcw’ on SI). Denosumab is the protagonist of AMGN’s pipeline; it goes to an FDA advisory panel on Aug 13 (#msg-38956103) and has a PDUFA date of Oct 19. Zometa is NVS’ third-largest drug (after Diovan and Gleevec) with annual sales of about $1.4B.]

›Conclusions — A recently published article (Fizazi et al, Journal of Urology) analyzed results from the ph 2 dmab trial in the subset of pts w/prostate cancer. Dmab showed a lower rate of skeletal-related events (SREs) vs. IV bisphosphonates (BPs) in these pts. This may suggest that dmab will be better than Zometa in the ongoing ph 3 study (data in H1:10). In breast and other cancer, dmab was similar to Zometa in the ph 2 study. Thus, we continue to view prostate cancer as the best opportunity for dmab.

Lower SREs — In the overall trial (n=111), pts received dmab or IV BPs (mostly Zometa). There was an 8% rate of SREs (1% prostate, 4% breast, and 3% other cancers) in pts treated w/dmab (n=73) vs. 20% rate (9% prostate, 6% breast, and 3% other cancers) in the IV BP arm (n=35).

Dmab Better in Prostate Cancer? — Dmab had a lower incidence of SRE in prostate cancer (n=33) vs. IV BPs (n=16) (1% vs 9%). This may suggest that dmab could be better than Zometa in the ongoing ph 3 trial (data in H1:10). In the prostate cancer subset, only 3% of pts (1/33) on dmab had an on-study SRE vs. 19% of pts on IV BPs (3/16).

Dmab in Breast/Other Cancers Looks Same — In breast cancer, in the ph 2 trial, the diff was modest (4% vs 6%) (data from the ph 3 trial expected in Aug ’09). There was also no diff in other cancers in the ph 2 (3% vs. 3%) (data from ph 3 trial expected in Q4:09).

Safety in All Tumors — In the ph 2 trial, dmab was found to be safe. There were slightly fewer infections with dmab vs. IV BPs (29% vs. 37%) and serious infections were 6% in dmab vs. 17% in IV BPs. Grade =3 adverse events occurred in 55% of dmab vs. 71% of IV BPs pts. Grade 3 hypocalcemia was seen in 8% of dmab pts vs. 3% with IV BPs. One patient developed a dmabrelated grade 4 serious adverse event (described below).

One Grade 4 in Prostate Cancer — In the prostate cancer subset, potentially treatment-related adverse events were reported in 27% of pts taking dmab vs 12% of pts on IV BPs. One pt experienced asymptomatic, transient lower phosphate levels (grade 4) with rapid cancer progression and high parathyroid hormone levels. In the dmab arm, there were no renal or hepatic issues and no ONJ (these are issues with BPs). Overall, the safety data is based on small pt numbers, but so far the data looks clean.‹