Validity of the Minnesota aGvHD risk score in predicting survival and response to therapy

The Minnesota acute graft-versus-host disease (aGvHD) risk score was developed to classify patients as standard- or high-risk of non-relapse mortality and response to therapy. The scoring system considers the number of organs involved and the severity of aGvHD at therapy onset, with standard-risk patients showing better outcomes.¹

At the 48th Annual Meeting of the European Society for Bone and Marrow Transplantation (EBMT), Maria Teresa Lupo-Stanghellini¹ presented a single-center study investigating the efficacy of this scoring system in the setting of posttransplant cyclophosphamide (PTCy). In this article we summarize the key results.

You can listen to a summary of the Minnesota risk score for GvHD in our interview with David Weisdorf here:

Methods

This prospective single-center study aimed to identify the accuracy of the Minnesota risk score in identifying patients at high-risk of aGvHD-associated mortality and response to steroid therapy. Inclusion criteria were:

• allogeneic hematopoietic stem cell transplants performed at San Raffaele Hospital, IT;
• recipients of PTCy-based GvHD prophylaxis for any disease indication;
• any donor type;
• and transplants performed between January 2016 and June 2020.

Results

Out of 315 eligible patients,  139 developed aGvHD, and their characteristics are summarized in Table 1.

Table 1. Characteristics of patients who developed aGvHD*

Multivariate analysis of all patients indicated that:

• the development of both Grades II–IV and III–IV aGvHD were impacted by donor source and donor age, with older donors associated with worse disease (Table 2);
• and the development of aGvHD Grade III–IV was affected by donor source (Table 2).

Table 2. Multivariate analysis of factors associated with aGvHD incidence*

Rates of 2-year overall survival and transplant-related mortality (TRM) stratified by Minnesota risk score revealed improved survival and lower TRM in patients with a standard risk score compared with those classified as high-risk (Figure 1).

Figure 1. The 2-year OS and TRM in Minnesota high- and standard-risk patients*

OS, overall survival; TRM, transplant-related mortality.
*Adapted from Lupo-Stanghellini.¹

When stratifying by Day 28 overall response rate, improved response rates were seen in the standard-risk cohort compared with the high-risk cohort (Figure 2).

Figure 2. Day 28 ORR in patients classified as standard- and high-risk by Minnesota score*

ORR, overall response rate.
*Adapted from Lupo-Stanghellini.¹

Conclusion

Results from this study validate the accuracy of using the Minnesota risk score as a tool for predicting Day 28 overall response rate, 2-year overall survival probability, and TRM in standard- and high-risk patients with aGvHD following PTCy. The authors suggested that this may be a better approach for identifying high-risk patients than using initial GvHD grade, allowing for more effective therapy.