Table 1.

Differences between LSA- and HSA-I-131-MIBG.

Characteristics	LSA-I-131-MIBG	HSA-I-131 MIBG
Manufacturing process	Simple isotope exchange methodology [47]	Solid phase precursor Ultratrace process [46]
Unlabeled MIBG in each dose	Large amount [46]	None [46]
Chemical mass of unlabeled amount of MIBG in a 500 mCi dose	~12 mg [46]	~0.2 mg [46]
Specific activity of final drug product	~1.59 MBq/μg (low) [44,46]	~92.5 MBq/μg (very high) [46]
Potential efficacy	Low levels of radioactivity delivered to tumor per dose [46]	High levels of radioactivity delivered to tumor per dose [46]
Potential safety	Excess cold MIBG and increased risk for cardiovascular issues [46]	No cold MIBG, low cardiovascular risk [46]