<p><strong> </strong><strong>In high-risk patients who completely respond to induction BCG, clinicians should continue maintenance BCG, based on availability, for three years, as tolerated. (<em>Moderate Recommendation; Evidence Level: Grade B</em>)</strong></p>
Discussion
Discussion
<p>Several meta-analyses have reported that the superiority of BCG compared to intravesical chemotherapy to prevent recurrence and progression of high-risk NMIBC is restricted to those patients who receive maintenance therapy.<sup>188, 234, 235</sup> The optimal schedule and duration of maintenance therapy is unknown. A 3-year maintenance schedule for those who can tolerate maintenance is supported by data from SWOG-8507<sup>236</sup> and EORTC-30962.<sup>213</sup> SWOG-8507 showed that maintenance BCG given as a weekly instillation for 3 weeks at 3, 6, 12, 18, 24, 30, and 36 months compared to induction BCG alone increased the 5-year recurrence-free survival from 41% to 60% (P<0.0001).<sup>236</sup> EORTC-30962, using a similar regimen, showed that high-risk patients (high-grade, T1) receiving 3 years of full-dose maintenance had an increased likelihood of remaining disease-free at 5 years compared to those receiving 1 year of maintenance (HR: 1.61; 95%CI: 1.13 to 2.30; P=0.009).<sup>213</sup> As noted previously in the POTOMAC trial, when durvalumab was added to BCG induction plus maintenance for 2 years, there was a 5% absolute improvement in disease-free survival at 24 months albeit at a higher risk of Grades 3-4 adverse events.<sup>215</sup></p>