Serum phosphorus calcium, magnesium and potassium >= lower limit of normal (LLN)Xx_NEWLINE_xXSerum calcium and magnesium above the institutional lower limit of normal, within 14 days of registration and within 7 days of the start of treatmentXx_NEWLINE_xXSerum phosphorus >= lower limit of normal (LLN)Xx_NEWLINE_xXCalcium >= LLNXx_NEWLINE_xXMagnesium >= LLNXx_NEWLINE_xXPotassium >= LLNXx_NEWLINE_xXSerum phosphorus, calcium, magnesium and potassium >= lower limit of normal (LLN)Xx_NEWLINE_xXSerum phosphorus >= lower limit of normal (LLN)Xx_NEWLINE_xXSerum calcium >= LLNXx_NEWLINE_xXSerum magnesium >= LLNXx_NEWLINE_xXSerum potassium >= LLNXx_NEWLINE_xXSerum phosphorus >= lower limit of normal (LLN) (if below LLN, for asymptomatic patients replacement may be initiated if clinically indicated without delaying the start of study treatment)Xx_NEWLINE_xXSerum calcium >= LLN (if below LLN, for asymptomatic patients replacement may be initiated if clinically indicated without delaying the start of study treatment)Xx_NEWLINE_xXSerum magnesium >= LLN (if below LLN, for asymptomatic patients replacement may be initiated if clinically indicated without delaying the start of study treatment)Xx_NEWLINE_xXSerum potassium >= LLN (if below LLN, for asymptomatic patients replacement may be initiated if clinically indicated without delaying the start of study treatment)Xx_NEWLINE_xXRECURRENT/ PROGRESSIVE DIPG (STRATUM 1): Potassium >= lower limit of normal (LLN)Xx_NEWLINE_xXRECURRENT/ PROGRESSIVE DIPG (STRATUM 1): Serum total calcium (correct for serum albumin) or ionized calcium >= LLNXx_NEWLINE_xXNON-PROGRESSED DIPG (STRATUM 2): Serum total calcium (correct for serum albumin) or ionized calcium >= LLNXx_NEWLINE_xX