The mm Hub website uses a third-party service provided by Google that dynamically translates web content. Translations are machine generated, so may not be an exact or complete translation, and the mm Hub cannot guarantee the accuracy of translated content. The mm and its employees will not be liable for any direct, indirect, or consequential damages (even if foreseeable) resulting from use of the Google Translate feature. For further support with Google Translate, visit Google Translate Help.
The Multiple Myeloma Hub is an independent medical education platform, sponsored by Bristol Myers Squibb, GSK, Johnson & Johnson, Pfizer, Roche and Sanofi. The levels of sponsorship listed are reflective of the amount of funding given. View funders.
Now you can support HCPs in making informed decisions for their patients
Your contribution helps us continuously deliver expertly curated content to HCPs worldwide. You will also have the opportunity to make a content suggestion for consideration and receive updates on the impact contributions are making to our content.
Find out moreCreate an account and access these new features:
Bookmark content to read later
Select your specific areas of interest
View mm content recommended for you
On Sunday 2 June, 2019, Professor Max Topp, University of Würzburg, Würzburg, DE, presented the results of the phase I trial of AMG 420 (BI 836909) in relapsed/refractory multiple myeloma (RRMM), at the annual American Society of Clinical Oncology (ASCO) meeting, in Chicago, US.
AMG 420 is a bispecific T-cell engager (BiTE®) antibody construct that binds to B-cell maturation antigen (BCMA) on tumor/plasma cells, and CD3 on T-cells. This dual action leads to T-cell mediated lysis of BCMA+ cells.
Table 1: Patient characteristics
ECOG, Eastern Cooperative Oncology Group; IMid, immunomodulatory drugs; PI, proteosome inhibitor |
|
|
N= 42 |
---|---|
Median age (year) |
65 (39–79) |
ECOG status (0 vs 1 vs 2) |
57% vs 40% vs 2% |
Cytogenetics (standard vs intermediate vs high) |
55% vs 31% vs 14% |
Median prior lines of therapy |
4 (2–13) |
Prior monoclonal antibody (daratumumab vs elotuzumab) |
26% vs 10% |
Refractory to monoclonal antibody (daratumumab vs elotuzumab) |
21% vs 10% |
Refractory to IMid/PI/IMid and PI |
55% vs 45% vs 31% |
Table 2 shows a summary of the three grade 3 DLTs that occurred. The MTD was determined to be 400μg/day. No anti-AMG 420 antibodies were detected up to 800μg/day.
Table 2: Summary of grade 3 DLTs
|
DLT |
Dose of AMG 420 |
Timing of DLT |
Notes |
---|---|---|---|---|
1 |
CRS |
800μg/day |
1 day after treatment start. Resolved after AMG 420 was discontinued |
Symptoms; fever, hypertension, tachycardia and retrograde amnesia |
2 |
Peripheral PN |
800μg/day |
1 week after treatment start, required hospitalization by day 14
|
M protein decreased by 58% after 15 days of treatment. PN resolved with IV Ig and corticosteroid |
3 |
PN |
400μg/day |
Grade 1 PN developed to grade 3 by day 30 and improved to baseline by day 84 |
M protein decreased by 79% after 28 days of treatment. PN resolved with IV Ig and corticosteroid |
CRS, cytokine relase syndrome; DLT, dose-limiting toxicities; PN, polyneuropathy |
The safety data for CRS, SAEs and treatment-related SAEs is shown in Table 3. Of the two patients who died of infection, one died of aspergillosis/flu and one died of fulminant hepatitis related to adenovirus infection. Neither were deemed to be treatment-related.
Of the 19 patients (45%) experiencing a SAE, 16 were hospitalized, 4 for a prolonged period. No grade 3–4 central nervous system toxicities were observed.
Table 3: CRS, SAEs and treatment-related SAEs grade 1–5 (N= 42)
CRS, cytokine relase syndrome; PN, polyneuropathy; SAEs, serious adverse events | ||||||
Grade |
Total |
1 |
2 |
3 |
4 |
5 |
---|---|---|---|---|---|---|
CRS |
16 (38%) |
13 |
2 |
1 |
- |
- |
SAEs (≥2 patients) |
|
|
|
|
|
|
Infections |
13 (31%) |
- |
3 |
8 |
- |
2 |
PN |
2 (5%) |
- |
- |
2 |
- |
- |
Treatment-related SAEs |
|
|
|
|
|
|
PN |
2 (5%) |
- |
- |
2 |
- |
- |
Edema |
1 (2%) |
- |
- |
1 |
- |
- |
Currently, two patients remain on therapy, with the remainder having discontinued for the following reasons; PD (n= 25, 60%), AEs (n= 7, 17%), death (n= 4, 10%), completion of 10 cycles (n= 3, 7%), and withdrawal of consent (n= 1, 2%). Deaths were attributable to disease progression (n= 2) and AEs (n= 2).
At a dose of 400μg/day (n= 10), 5 MRD negative complete responses (CRs) were seen, with 1 very good partial response (VGPR) and 1 partial response (PR) giving a response rate of 70%, lasting for a median of 9.0 months (5.8–13.6).
In total, 13 patients responded (13/42), with a median time to response of 1 month, lasting for 8.4 months on average (2.5–15.5). MRD negative CRs lasted for a median of 9.6 months (2.8–12.8), with 5 of these patients in the 400μg/day cohort. Aside from the patients whose last response at evaluation was PD (n= 5), all patients were responding.
Responses at doses less than 200μg/day were:
Table 4: Characteristics of responding patients at doses ≥200μg/day
CR, complete response; EOT; end of treatment, N/A; patient received 10 cycles or treatment ongoing as of April 2019 (maximum); MRD, minimum measurable disease; PD, progressive disease; PN, polyneuropathy; PR, partial response; VGPR, very good partial response | |||||
Dose (μg/day) |
Number of cycles to response |
Prior lines of therapy |
Reason for discontinuation |
Best response |
Cycle of best response |
---|---|---|---|---|---|
200 |
4 |
6 |
Port infection |
MRD- CR |
3–4 to 11 months post-treatment |
400 |
7 |
3 |
N/A |
MRD- CR |
3–7 |
400 |
10 |
4 |
N/A |
MRD- CR |
3–10 |
400 |
8 |
6 |
PD |
MRD- CR |
1–7 |
400 |
10 |
2 |
N/A |
MRD- CR |
1–10 |
400 |
5 |
5 |
PD |
MRD- CR |
3–4 |
400 |
1 |
5 |
PN |
VGPR |
From EOT to 7 months post-EOT |
400 |
1 |
5 |
Death |
PR |
1 |
800 400 (dose reduction) |
2 1 |
5 |
Withdrew consent |
VGPR |
2–3 |
800 |
0.5 |
5 |
PN |
PR and CR |
PR in 1, CR 9 months post-EOT |
AMG 420 demonstrates activity in a heavily pre-treated population with RRMM who had received, on average, 4 prior lines of therapy. At the MTD of 400μg/day there was a 70% response rate, with 5 patients achieving MRD negative CR. No major toxicities were reported in the dose escalation portion of the study, subsequently DLTs were experienced by three patients. In addition, 13 (31%) patients experienced infections, 10 of which were grade 3 or above. Professor Topp suggested that future clinical trials of AMG 420 should thoroughly evaluate infection risk in order to best inform AE management guidelines. A phase Ib/II trial is ongoing.
References